PERFECT TENSE

Usage :
1. To talk about a completed past action at a non- specific time
example : I have read that book before
2. It is used to express personal experience there is not a definite time given.
example : I have ever visited Surabaya.
3. To talk about something that began in the past and continues to the present.
example : I have studied in this school since last
June .

Structure
(+) S + Have/has + Past Participle + O
(-) S + Have/Has + Not + Past Participle + O
(?) Have/has + S + Past participle + O ?

EXAMPLE :
She has worked in that office for six years.

(+) I have written my letter

(-) I have not written my letter

(?) Have you written your later?

For irregular verbs, use the participle form (see list of irregular verbs, 3rd column). For regular verbs, just add “ed”.

Adverbs :
• for refers to a period of time.
example : I have known him for many years
• since refers to the time when the events started.
example : I have learned english since 10 years old.
• just means that something happened a moment ago.
example : she has just left the school.
• already means that something happens earlier than expected.
example : he has already handed in the assignment.
• yet means that up to the present time something has not happened (only in question or negative sentences).
example : he hasn’t sent the letter yet.

Past Perfect Tense :

Usage :

We use the past perfect to talk about an action which happened before another action in the past

Structure :

(+) S + Had + Past Participle + O

(-) S + Had + Not + Past Participle + O

(?) Had + S + Past participle + O ?

Example :

• I hadn’t studied english when she came to my house last night.
• He had washed his uncle’s car before his uncle arrived last Sunday.
• Had Susan ever studied Thai before she moved to Thailand?

The key words of this tense are:

after

as soon as {had+PP} Past simple

Example :

• After I had finished my work ,I watched TV
• As soon as I had eaten my breakfast,I went to school

The key words of this tense are:

before

By the time {past simple} + Had+PP

Example :

• Before I watched TV ,I had finished my work.
• By the time I went to school,I had eaten my breakfast.

The key words of this tense are:

Had+PP + When + Past Simple

Example :

• Sam had already left when we got there.

Adverbs

• Last night
• Last week
• Last month
• Last Saturday
• Yesterday