22 Eylül 2012 Cumartesi

THE PRESENT PERFECT TENSE

1. Use :

The English Present Perfect tense is used to express actions which have just or already been completed at the time of speaking or writing.
--> I have done the work.
--> She has answered half the questions.

In the first example, the use of the Present Perfect tense emphasizes the fact that, at the time of speaking or writing, the work has already been completed. In the second example, the use of the Present Perfect indicates that, at the time of speaking or writing, half the questions have been answered.

This tense epresses the very recent past:
--> They've just left.

It also tells of a state or situation which has started in the past and is continuing up to now:
--> I have lived there for a long time. (I am still living there.)

The event may be a finished state or activity but the period of time in which it has taken place is not finished:
--> I have written a letter this morning. (the letter is finished and it is still morning)

It tells about an event with a present result :
--> I have lost my keys.

  2. Formation of the present perfect: Regular verbs
The Present Perfect tense of any English verb is formed from the Simple Present of the auxiliary to have, followed by what is generally referred to as the past participle of the verb.

Most English verbs form the past participle in a regular, predictable manner. These verbs are commonly referred to as regular verbs.

The past participle of a regular English verb is formed by adding the ending ed to the bare infinitive of the verb. For instance, the past participle of the verb to work is worked.

Thus, the Present Perfect tense of the verb to work is conjugated as follows:


I have worked
you have worked
he has worked
she has worked
it has worked
we have worked
they have worked

The following contractions are often used in spoken English:

Without Contractions With Contractions
  I have   I've
  you have   you've
  he has   he's
  she has   she's
  it has   it's
  we have   we've
  they have   they've

It should be noted that the contractions for he has, she has and it has are the same as the contractions for he is, she is and it is.


  3. Spelling rules for adding ed to form the past participle
Some regular verbs change their spelling when the ending ed is added to form the past participle.

a. Verbs ending in a silent e
When a regular verb ends in a silent e, only the letter d must be added in order to form the past participle. For example:


Infinitive Past Participle
  to close   closed
  to move   moved
  to please   pleased
  to receive   received

b. Verbs ending in y
When a regular verb ends in y immediately preceded by a consonant, the y is changed to i before the ending ed is added. For example:

Infinitive Past Participle
  to study   studied
  to rely   relied
  to carry   carried

However, when a regular verb ends in y immediately preceded by a vowel, the y is not changed before the ending ed is added. For example:

Infinitive Past Participle
  to play   played
  to convey   conveyed
  to enjoy   enjoyed


c. Verbs ending in a single consonant preceded by a single vowel
The rules concerning the doubling of final consonants which apply when adding the ending ing to form the present participle also apply when adding the ending ed to form the past participle.

Thus, when a one-syllable verb ends in a single consonant other than w, x or y immediately preceded by a single vowel, the final consonant must be doubled before the ending ed is added to form the past participle. In the following examples, the consonants which have been doubled are underlined. For example:

Infinitive Past Participle
  to rub   rubbed
  to trim   trimmed
  to plan   planned
  to stop   stopped

When a verb of more than one syllable ends in a single consonant other than w, x or y immediately preceded by a single vowel, the final consonant is doubled before the ending ed only when the last syllable of the verb is pronounced with the heaviest stress. In the following examples, the syllables pronounced with the heaviest stress are underlined. For example:

Infinitive Past Participle
  to control   controlled
  to infer   inferred
  to occur   occurred
  to permit   permitted
  to fasten   fastened
  to order   ordered
  to focus   focused
  to limit   limited

In the first four examples, the last syllable of the verb is pronounced with the heaviest stress, and the final consonant is doubled before ed is added. In the last four examples, the first syllable of the verb is pronounced with the heaviest stress, and the final consonant is not doubled before ed is added.

The final consonants w, x and y are never doubled when the ending ed is added. For example:

Infinitive Past Participle
  to follow   followed
  to box   boxed
  to portray   portrayed

It should also be noted that final consonants immediately preceded by two vowels are not doubled when the ending ed is added. For example:

Infinitive Past Participle
  to greet   greeted
  to rain   rained
  to soak   soaked
  to treat   treated


  4. Pronunciation of the ed ending
The ending ed is usually not pronounced as a separate syllable. For instance, in each of the following examples, both the bare infinitive and the past participle consist of one syllable. For example:


Bare Infinitive Past Participle
  puff   puffed
  work   worked
  miss   missed
  watch   watched

However, when the ending ed is added to verbs which end in d or t, the ed ending of the past participle is pronounced as a separate syllable. The reason for this is that the sounds of d and t are so similar to the sound of the ed ending, that the ending must be pronounced as a separate syllable in order to be heard clearly.

In each of the following examples, the bare infinitive consists of one syllable; whereas the past participle consists of two syllables. For example:

Bare Infinitive Past Participle
  add   added
  land   landed
  hunt   hunted
  wait   waited

Similarly, when d is added to verbs ending in a silent e preceded by d or t, the final ed of the past participle is pronounced as a separate syllable. In each of the following examples, the bare infinitive consists of one syllable; whereas the past participle consists of two syllables. For example:

Bare Infinitive Past Participle
  fade   faded
  glide   glided
  cite   cited
  note   noted


  5. Formation of the present perfect: Irregular verbs
In addition to regular English verbs, there are many irregular English verbs, which do not form the past participle with the ending ed. The English irregular verbs are related to the strong verbs of the German language. The following are examples of irregular English verbs. For example:


Bare Infinitive Past Participle
  begin   begun
  find   found
  go   gone
  let   let
  take   taken

The past participles of irregular English verbs are formed in an unpredictable manner, and must be memorized.

Except for the irregularity of the past participle, the formation of the Present Perfect tense is the same for an irregular verb as for a regular verb. In both cases, the Simple Present of the auxiliary to have is followed by the past participle of the verb.

For instance, the irregular verb to take has the past participle taken. Thus, the Present Perfect of the irregular verb to take is conjugated as follows:

 I have taken
 you have taken
 he has taken
 she has taken
 it has taken
 we have taken
 they have taken


  6. Questions and negative statements
As is the case with other English tenses, questions and negative statements in the Present Perfect are formed using the auxiliary. In the case of the Present Perfect, the auxiliary is have or has.

a. Questions
In order to form a question, the auxiliary is placed before the subject of the verb. For example:


Affirmative Statement Question
  I have worked.   Have I worked?
  You have worked.   Have you worked?
  He has worked.   Has he worked?
  She has worked.   Has she worked?
  It has worked.   Has it worked?
  We have worked.   Have we worked?
  They have worked.   Have they worked?

b. Negative statements
In order to form a negative statement, the word not is placed after the auxiliary. For example:

Affirmative Statement Negative Statement
  I have worked.   I have not worked.
  You have worked.   You have not worked.
  He has worked.   He has not worked.
  She has worked.   She has not worked.
  It has worked.   It has not worked.
  We have worked.   We have not worked.
  They have worked.   They have not worked.

The following contractions are often used in spoken English:

Without Contractions With Contractions
  have not   haven't
  has not   hasn't

c. Negative questions
In order to form a negative question, the auxiliary is placed before the subject, and the word not is placed after the subject. However, when contractions are used, the contracted form of not follows immediately after the auxiliary. For example:

Without Contractions With Contractions
  Have I not worked?   Haven't I worked?
  Have you not worked?   Haven't you worked?
  Has he not worked?   Hasn't he worked?
  Has she not worked?   Hasn't she worked?
  Has it not worked?   Hasn't it worked?
  Have we not worked?   Haven't we worked?
  Have they not worked?   Haven't they worked?

Hiç yorum yok:

Yorum Gönder