Past Perfect

We use the past perfect

1. For actions/states before a time in the past:

By the third month the rebels had taken most of the province.

2. For an earlier action in a past sequence:

When we got back the babysitter had gone home.

3. For unfulfilled intentions:

They had hoped to reach the summit but Travers fell ill.

4. For an action which finished in the past and whose result was visible in the past:

Jim was happy. He had signed an important contract.(The action finished in the past and its result was visible in the past, too.)

5. To show that the action of the main clause stopped only after the action of the subordinate clause was accomplished:

He waited till she had regained a certain calm.

6. In the sentence pattern which is a complex sentence with a subordinate clause of time introduced by scarcely…when; hardly…when; nearly…when; barely…when; no sooner…than, the time relation between the two actions is of a specific character – the action of the subordinate clause takes place when the action of the principle clause is hardly accomplished yet. Hence, the Past Perfect is found in the principle clause and the Past Simple in the subordinate clause:

He had scarcely entered the room when in a chair by the door he perceived Ann Chester.

7. To show that the action of the principal clause precedes that of the ’before-clause’. The Past Perfect is found in the principal clause and the Past Simple in the subordinate clause:

He had heard the news before he ran up my stairs.

There may be a specific time relation between the two actions in a complex sentence with a ’before-clause’. The action in one of the clauses is not fully accomplished before the action of the other clause takes place.The unaccomplished action is expressed by the Past Perfect. If the unaccomplished action is expressed in the principal clause, its predicate is always negative in form:

They had not gone four miles before he understood it was going to rain.

If the unaccomplished action is expressed in the subordinate clause, its predicate is affirmative in form but negative in meaning:

I discovered the news before I had been in the house for an hour.

Future Perfect

We use the Future Perfect

1. To talk about an action completed by a point in the future:

I will have finished this report by 3.30.

2. To talk about an assumption on the part of the speaker:

You won’t have heard the news, of course. (=I assume you have not heard the news.)

The Future Perfect is used with the following time expressions: before, by, by then,

by the time, until/till.

Note: Until/till are only used in negative sentences:

She won’t have completed the report until/till 5 o’clock.

Present Perfect Continuous

We use the Present Perfect Continuous

1. To talk about ongoing states and actions:

Women have been speaking out on this issue for some time.

2. To talk about ongoing actions/states which are temporary or may change:

She’s been drinking a lot recently.

3. To focus on the duration of a continuing action:

I’ve been learning to play chess for three years now.

4. To talk about recent actions:

I’ve been talking to Jenny.

5. To explain a present result (focus on the activity):

I’m sorry the hall is in such a mess. We’ve been decorating.

6. To express anger, irritation or annoyance:

Somebody has been giving away our plans.

Note: with the verbs live, work, teach and feel (=have a particular emotion) we can use the present perfect or present perfect continuous with no difference in meaning:

We have lived/have been living here for twenty years.

The present perfect continuous is used with the following time expressions: for, since, how long, lately, recently.