วันพุธที่ 15 กุมภาพันธ์ พ.ศ. 2555

Conjunctions

Conjunctions






A conjunction is a word that "joins". A conjunction joins two parts of a sentence.

Here are some example conjunctions:

Coordinating Conjunctions Subordinating Conjunctions
and, but, or, nor, for, yet, so although, because, since, unless

We can consider conjunctions from three aspects.





Form




Conjunctions have three basic forms:

  • Single Word
    for example: and, but, because, although
  • Compound (often ending with as or that)
    for example: provided that, as long as, in order that
  • Correlative (surrounding an adverb or adjective)
    for example: so...that


Function



Conjunctions have two basic functions or "jobs":

  • Coordinating conjunctions are used to join two parts of a sentence that are grammatically equal. The two parts may be single words or clauses, for example:
    - Jack and Jill went up the hill.
    - The water was warm, but I didn't go swimming.
  • Subordinating conjunctions are used to join a subordinate dependent clause to a main clause, for example:
    - I went swimming although it was cold.


Position



  • Coordinating conjunctions always come between the words or clauses that they join.
  • Subordinating conjunctions usually come at the beginning of the subordinate clause.

In this lesson we will look in more detail at:





Coordinating Conjunctions


The short, simple conjunctions are called "coordinating conjunctions":
  • and, but, or, nor, for, yet, so
A coordinating conjunction joins parts of a sentence (for example words or independent clauses) that are grammatically equal or similar. A coordinating conjunction shows that the elements it joins are similar in importance and structure:
+
Look at these examples - the two elements that the coordinating conjunction joins are shown in square brackets [ ]:
  • I like [tea] and [coffee].
  • [Ram likes tea], but [Anthony likes coffee].
Coordinating conjunctions always come between the words or clauses that they join.
When a coordinating conjunction joins independent clauses, it is always correct to place a comma before the conjunction:
  • I want to work as an interpreter in the future, so I am studying Russian at university.
However, if the independent clauses are short and well-balanced, a comma is not really essential:
  • She is kind so she helps people.
When "and" is used with the last word of a list, a comma is optional:
  • He drinks beer, whisky, wine, and rum.
  • He drinks beer, whisky, wine and rum.
The 7 coordinating conjunctions are short, simple words. They have only two or three letters. There's an easy way to remember them - their initials spell:
F A N B O Y S
For And Nor But Or Yet So




Subordinating Conjunctions


The majority of conjunctions are "subordinating conjunctions". Common subordinating conjunctions are:
  • after, although, as, because, before, how, if, once, since, than, that, though, till, until, when, where, whether, while
A subordinating conjunction joins a subordinate (dependent) clause to a main (independent) clause:
+
Look at this example:

main or
independent clause
subordinate or
dependent clause
Ram went swimming although it was raining.
subordinating
conjunction
A subordinate or dependent clause "depends" on a main or independent clause. It cannot exist alone. Imagine that somebody says to you: "Hello! Although it was raining." What do you understand? Nothing! But a main or independent clause can exist alone. You will understand very well if somebody says to you: "Hello! Ram went swimming."
A subordinating conjunction always comes at the beginning of a subordinate clause. It "introduces" a subordinate clause. However, a subordinate clause can sometimes come after and sometimes before a main clause. Thus, two structures are possible:


+

Ram went swimming although it was raining.
+

Although it was raining, Ram went swimming.
















Punctuation

Punctuation


Why do we need punctuation?
Punctuation marks are essential when you are writing. They show the reader where sentences start and finish and if they are used properly they make your writing easy to understand. This section gives practical guidance on how to use commas, semicolons, and other types of punctuation correctly, so that your writing will always be clear and effective.
You may find some aspects of punctuation harder to grasp than others (for example, when to use a semicolon or a colon). If so, just click on the relevant heading in the list to the left. There are also handy sections with advice on using punctuation when writing direct speech, lists, or abbreviations.
Types of punctuation
See also























Comparison

Comparison

Comparison of adjectives



Adjectives - Comparison - Exercise 1 Exercise 2 Exercise 3
Adjectives - Comparison in sentences - Exercise 1 Exercise 2
Adjectives - Comparison with -er and -est - Exercise 1 Exercise 2
Adjectives - Words randomly selected - Exercise 1 Exercise 2 Exercise 3


There are three forms of comparison:

- positive
- comparative
- superlative




A - Comparison with -er/-est

clean - cleaner - (the) cleanest

We use -er/-est with the following adjectives:



1) adjectives with one syllable



clean cleaner cleanest
new newer newest
cheap cheaper cheapest

2) adjectives with two syllables and the following endings:


2 - 1) adjectives with two syllables, ending in -y



dirty dirtier dirtiest
easy easier easiest
happy happier happiest
pretty prettier prettiest

2 - 2) adjectives with two syllables, ending in -er



clever cleverer cleverest

2 - 3) adjectives with two syllables, ending in -le



simple simpler simplest

2 - 4) adjectives with two syllables, ending in -ow



narrow narrower narrowest





Spelling of the adjectives using the endings -er/-est


large larger largest leave out the silent -e
big bigger biggest Double the consonant after short vowel
sad sadder saddest
dirty dirtier dirtiest Change -y to -i (consonant before -y)
shy shyer shyest Here -y is not changed to -i.
(although consonant before -y)


B - Comparison with more - most

difficult - more difficult - (the) most difficult
all adjectives with more than one syllable (except some adjectives with two syllables - see
2 - 1 to 2 - 4)


C - Irregular adjectives


good better best
bad worse worst
much more most uncountable nouns
many more most countable nouns
little less least
little smaller smallest


D - Special adjectives

Some ajdectives have two possible forms of comparison.
common commoner / more common commonest / most common
likely likelier / more likely likeliest / most likely
pleasant pleasanter / more pleasant pleasantest / most pleasant
polite politer / more polite politest / most polite
simple simpler / more simple simplest / most simple
stupid stupider / more stupid stupidest / most stupid
subtle subtler / more subtle subtlest
sure surer / more sure surest / most sure


Difference in meaning with adjectives:



far farther farthest distance
further furthest distance or
time
late later latest
latter x
x last
old older oldest people and things
elder eldest people (family)
near nearer nearest distance
x next order


























Auxiliary Verbs or Helping

 Auxiliary Verbs or Helping 



Helping verbs or auxiliary verbs such as will, shall, may, might, can, could, must, ought to, should, would, used to, need are used in conjunction with main verbs to express shades of time and mood. The combination of helping verbs with main verbs creates what are called verb phrases or verb strings. In the following sentence, "will have been" are helping or auxiliary verbs and "studying" is the main verb; the whole verb string is underlined:
  • As of next August, I will have been studying chemistry for ten years.
Students should remember that adverbs and contracted forms are not, technically, part of the verb. In the sentence, "He has already started." the adverb already modifies the verb, but it is not really part of the verb. The same is true of the 'nt in "He hasn't started yet" (the adverb not, represented by the contracted n't, is not part of the verb, has started).
Shall, will and forms of have, do and be combine with main verbs to indicate time and voice. As auxiliaries, the verbs be, have and do can change form to indicate changes in subject and time.
  • I shall go now.
  • He had won the election.
  • They did write that novel together.
  • I am going now.
  • He was winning the election.
  • They have been writing that novel for a long time.

Uses of Shall and Will and Should

In England, shall is used to express the simple future for first person Iand we, as in "Shall we meet by the river?" Will would be used in the simple future for all other persons. Using will in the first person would express determination on the part of the speaker, as in "We will finish this project by tonight, by golly!" Using shall in second and third persons would indicate some kind of promise about the subject, as in "This shall be revealed to you in good time." This usage is certainly acceptable in the U.S., although shall is used far less frequently. The distinction between the two is often obscured by the contraction 'll, which is the same for both verbs.
In the United States, we seldom use shall for anything other than polite questions (suggesting an element of permission) in the first-person:
  • "Shall we go now?"
  • "Shall I call a doctor for you?"
(In the second sentence, many writers would use should instead, although should is somewhat more tentative than shall.) In the U.S., to express the future tense, the verb will is used in all other cases.
Shall is often used in formal situations (legal or legalistic documents, minutes to meetings, etc.) to express obligation, even with third-person and second-person constructions:
  • The board of directors shall be responsible for payment to stockholders.
  • The college president shall report financial shortfalls to the executive director each semester."
Should is usually replaced, nowadays, by would. It is still used, however, to mean "ought to" as in
  • You really shouldn't do that.
  • If you think that was amazing, you should have seen it last night.
In British English and very formal American English, one is apt to hear or read should with the first-person pronouns in expressions of liking such as "I should prefer iced tea" and in tentative expressions of opinion such as
  • I should imagine they'll vote Conservative.
  • I should have thought so.
(The New Fowler's Modern English Usage edited by R.W. Burchfield. Clarendon Press: Oxford, England. 1996. Used with the permission of Oxford University Press. Examples our own.)

Uses of Do, Does and Did

In the simple present tense, do will function as an auxiliary to express the negative and to ask questions. (Does, however, is substituted for third-person, singular subjects in the present tense. The past tense didworks with all persons, singular and plural.)
  • I don't study at night.
  • She doesn't work here anymore.
  • Do you attend this school?
  • Does he work here?
These verbs also work as "short answers," with the main verb omitted.
  • Does she work here? No, she doesn't work here.
With "yes-no" questions, the form of do goes in front of the subject and the main verb comes after the subject:
  • Did your grandmother know Truman?
  • Do wildflowers grow in your back yard?
Forms of do are useful in expressing similarity and differences in conjunction with so and neither.
  • My wife hates spinach and so does my son.
  • My wife doesn't like spinach; neither do I.
Do is also helpful because it means you don't have to repeat the verb:
  • Larry excelled in language studies; so did his brother.
  • Raoul studies as hard as his sister does.
The so-called emphatic do has many uses in English.
  1. To add emphasis to an entire sentence: "He does like spinach. He really does!"
  2. To add emphasis to an imperative: "Do come in." (actually softens the command)
  3. To add emphasis to a frequency adverb: "He never didunderstand his father." "She always does manage to hurt her mother's feelings."
  4. To contradict a negative statement: "You didn't do your homework, did you?" "Oh, but I did finish it."
  5. To ask a clarifying question about a previous negative statement: "Ridwell didn't take the tools." "Then who did take the tools?"
  6. To indicate a strong concession: "Although the Clintons denied any wrong-doing, they did return some of the gifts."
In the absence of other modal auxiliaries, a form of do is used in question and negative constructions known as the get passive:
  • Did Rinaldo get selected by the committee?
  • The audience didn't get riled up by the politician.
Based on descriptions in Grammar Dimensions: Form, Meaning, and Use 2nd Ed. by Jan Frodesen and Janet Eyring. Heinle & Heinle: Boston. 1997. Examples our own.

Uses of Have, Has and Had

Forms of the verb to have are used to create tenses known as thepresent perfect and past perfect. The perfect tenses indicate that something has happened in the past; the present perfect indicating that something happened and might be continuing to happen, the past perfect indicating that something happened prior to something else happening. (That sounds worse than it really is!) See the section onVerb Tenses in the Active Voice for further explanation; also review material in the Directory of English Tenses.
To have is also in combination with other modal verbs to express probability and possibility in the past.
  • As an affirmative statement, to have can express how certain you are that something happened (when combined with an appropriate modal + have + a past participle): "Georgia must have left already." "Clinton might have known about the gifts." "They may have voted already."
  • As a negative statement, a modal is combined with not + have + a past participle to express how certain you are that something did not happen: "Clinton might not have known about the gifts." "I may not have been there at the time of the crime."
  • To ask about possibility or probability in the past, a modal is combined with the subject + have + past participle: "Could Clinton have known about the gifts?"
  • For short answers, a modal is combined with have: "Did Clinton know about this?" "I don't know. He may have." "The evidence is pretty positive. He must have."
To have (sometimes combined with to get) is used to express a logical inference:
  • It's been raining all week; the basement has to be flooded by now.
  • He hit his head on the doorway. He has got to be over seven feet tall!
Have is often combined with an infinitive to form an auxiliary whose meaning is similar to "must."
  • I have to have a car like that!
  • She has to pay her own tuition at college.
  • He has to have been the first student to try that.
    Based on the analysis in Grammar Dimensions: Form, Meaning, and Use 2nd Ed. by Jan Frodesen and Janet Eyring. Heinle & Heinle: Boston. 1997. Examples our own.

    Modal Auxiliaries

    Other helping verbs, called modal auxiliaries or modals, such as can, could, may, might, must, ought to, shall, should, will, and would, do not change form for different subjects. For instance, try substituting any of these modal auxiliaries for can with any of the subjects listed below.
    I
    you (singular)
    he
    we
    you (plural)
    they
    can write well.
    There is also a separate section on the Modal Auxiliaries, which divides these verbs into their various meanings of necessity, advice, ability, expectation, permission, possibility, etc., and provides sample sentences in various tenses. See the section on Conditional Verb Forms for help with the modal auxiliary would. The shades of meaning among modal auxiliaries are multifarious and complex. Most English-as-a-Second-Language textbooks will contain at least one chapter on their usage. For more advanced students, A University Grammar of English, by Randolph Quirk and Sidney Greenbaum, contains an excellent, extensive analysis of modal auxiliaries.
    The analysis of Modal Auxiliaries is based on a similar analysis in The Scott, Foresman Handbook for Writersby Maxine Hairston and John J. Ruszkiewicz. 4th ed. HarperCollins: New York. 1996. The description of helping verbs on this page is based on The Little, Brown Handbook by H. Ramsay Fowler and Jane E. Aaron, & Kay Limburg. 6th ed. HarperCollins: New York. 1995. By permission of Addison-Wesley Educational Publishers Inc. Examples in all cases are our own.

    Uses of Can and Could

    The modal auxiliary can is used
    • to express ability (in the sense of being able to do something or knowing how to do something):
      He can speak Spanish but he can't write it very well.
    • to expression permission (in the sense of being allowed or permitted to do something):
      Can I talk to my friends in the library waiting room? (Note that canis less formal than may. Also, some writers will object to the use ofcan in this context.)
    • to express theoretical possibility:
      American automobile makers can make better cars if they think there's a profit in it.
    The modal auxiliary could is used
    • to express an ability in the past:
      I could always beat you at tennis when we were kids.
    • to express past or future permission:
      Could I bury my cat in your back yard?
    • to express present possibility:
      We could always spend the afternoon just sitting around talking.
    • to express possibility or ability in contingent circumstances:
      If he studied harder, he could pass this course.
    In expressing ability, can and could frequently also imply willingness: Can you help me with my homework?

    Can versus May

    Whether the auxiliary verb can can be used to express permission or not — "Can I leave the room now?" ["I don't know if you can, but you may."] — depends on the level of formality of your text or situation. As Theodore Bernstein puts it in The Careful Writer, "a writer who is attentive to the proprieties will preserve the traditional distinction: can for ability or power to do something, may for permission to do it.
    The question is at what level can you safely ignore the "proprieties." Merriam-Webster's Dictionary, tenth edition, says the battle is over andcan can be used in virtually any situation to express or ask for permission. Most authorities, however, recommend a stricter adherence to the distinction, at least in formal situations.
    Authority: The Careful Writer by Theodore Bernstein. The Free Press: New York. 1998. p. 87.

    Uses of May and Might

    Two of the more troublesome modal auxiliaries are may and might. When used in the context of granting or seeking permission, might is the past tense of may. Might is considerably more tentative than may.
    • May I leave class early?
    • If I've finished all my work and I'm really quiet, might I leave early?
    In the context of expressing possibility, may and might are interchangeable present and future forms and might + have + past participle is the past form:
    • She might be my advisor next semester.
    • She may be my advisor next semester.
    • She might have advised me not to take biology.
    Avoid confusing the sense of possibility in may with the implication ofmight, that a hypothetical situation has not in fact occurred. For instance, let's say there's been a helicopter crash at the airport. In his initial report, before all the facts are gathered, a newscaster could say that the pilot "may have been injured." After we discover that the pilot is in fact all right, the newscaster can now say that the pilot "might have been injured" because it is a hypothetical situation that has not occurred. Another example: a body had been identified after much work by a detective. It was reported that "without this painstaking work, the bodymay have remained unidentified." Since the body was, in fact, identified,might is clearly called for.

    Uses of Will and Would

    In certain contexts, will and would are virtually interchangeable, but there are differences. Notice that the contracted form 'll is very frequently used for will.
    Will can be used to express willingness:
    • I'll wash the dishes if you dry.
    • We're going to the movies. Will you join us?
    It can also express intention (especially in the first person):
    • I'll do my exercises later on.
    and prediction:
    • specific: The meeting will be over soon.
    • timeless: Humidity will ruin my hairdo.
    • habitual: The river will overflow its banks every spring.

    Would can also be used to express willingness:
    • Would you please take off your hat?
    It can also express insistence (rather rare, and with a strong stress on the word "would"):
    • Now you've ruined everything. You would act that way.
    and characteristic activity:
    • customary: After work, he would walk to his home in West Hartford.
    • typical (casual): She would cause the whole family to be late, every time.
    In a main clause, would can express a hypothetical meaning:
    • My cocker spaniel would weigh a ton if I let her eat what she wants.
    Finally, would can express a sense of probability:
    • I hear a whistle. That would be the five o'clock train.

    Uses of Used to

    The auxiliary verb construction used to is used to express an action that took place in the past, perhaps customarily, but now that action no longer customarily takes place:
    • We used to take long vacation trips with the whole family.
    The spelling of this verb is a problem for some people because the "-ed" ending quite naturally disappears in speaking: "We yoostoo take long trips." But it ought not to disappear in writing. There are exceptions, though. When the auxiliary is combined with another auxiliary, did, the past tense is carried by the new auxiliary and the "-ed" ending is dropped. This will often happen in the interrogative:
    • Didn't you use to go jogging every morning before breakfast?
    • It didn't use to be that way.
    Used to can also be used to convey the sense of being accustomed to or familiar with something:
    • The tire factory down the road really stinks, but we're used to it by now.
    • I like these old sneakers; I'm used to them.
    Used to is best reserved for colloquial usage; it has no place in formal or academic text.

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    Prefixes and Suffixes

    Prefixes and Suffixes




    A prefix is a group of letters added before a word or base to alter its meaning and form a new word. In contrast, a suffix is a group of letters added after a word or base. This page contains free worksheets, online activities and other educational resources to help with prefixes and suffixes.



    Prefixes and Suffixes Word Lists (PDF)
    anti-de-dis-ex-mis--ly
    pre-re-un--ful-less

    Prefixes and Suffixes Links
    BBC Skillswise: Prefixes - Factsheets, a game, quiz and photocopiable activity from the BBC.BBC Skillswise: Suffixes - Factsheets, a quiz and some photocopiable activities.