All about Past Tenses

Simple Past tense

Form

The simple past form of  regular verb is verb+ d/Ed

Love - loved, work - worked

The simple past of irregular verb is different

Go - went, draw - drew, give - gave

The simple past of have is had; of be is was/were; of can is could or was/were + able to. 

Uses

1. This tense is used for a past action when the time of an action is mentioned. 

The screening of the film started at 7 p.m. 

In such sentence an adverb of time is often used. 

Simple past indicates completion of an action in the immediate or remote past:

Rama returned yesterday. 

Newton saw an apple fall.

Past perfect is not used to indicate completion of a single action even in remote past. 

So if we say 

Newton had seen an apple fall. (it is wrong) 

2. Simple past is usually used in questions about past actions or event:

Where did you stay in Delhi? 

Why did you laugh suddenly? 

Note

Who/what used as subject doesn't require a dummy auxiliary "did":

Who cleaned the floor? 

We do not say (who did clean the floor?) 

What happened there? Not (what did happen there?) 

Note we do not use the past perfect to ask questions about a past action, simple past is used

Where had you bought this camera? - wrong

Where did you buy this camera? - right

3. Simple past is often used in answer to questions in the present perfect form:

Have you heard the news? 

Yes, I have. I heard it just an hour ago. 

4. Simple past is used to refer to past habit. In such sentences we use an adverbial of frequency. 

Jim never came late for dance classes

5. Simple past is also used in conditional sentences to indicate an improbable condition:

If a ghost appeared we would scream

Simple past here indicate future time.

Past continuous tense

Form

The past continuous form of a verb is was/were + present participle

The past continuous form of have is was/were + having

Uses

Past continuous tense is used to indicate that an action was in progress for some time in the past:

The girls were singing and dancing.

Past Perfect Tense

Form

The past perfect form of a verb is had + past participle

The past perfect form of verb have is had + had

The past perfect form of verb be is had been

When have + noun means ' to experience/to take/to receive' its past perfect form is had + had + noun

I had had a lot of visitors last week

Means 

I had received a lot of visitors last week. 

Uses

1. Past perfect is used to report complete actions or events that happened before another point in the past. 

The chief guest arrived at 5 p. m. Our team had scored two goals already

2. Simple past becomes past perfect in the indirect speech when the reporting verb is in the past tense:

Rohan said, ' I prepared hard for the exams. '

Rohan said that he had prepared hard for the exams. 

3. Past perfect is used to indicate that one action had been completed before another started. Past perfect is used with the earlier action and simple past with the later action. 

The bus left at 7 p.m. We got to the bus station at 7.15 p.m.

Both sentences have been written in simple past tense. If we combine both sentences into one, the sentence will be

The bus had left when we got to the bus station. 

A sentence like the one written above uses these subordinating conjunctions: after, before, as soon as, till, until, when

I had consulted my lawyer(earlier action) before I lodged the complaint. ( later action) 

Note

4.When two past actions occur simultaneously or one action follows another immediately ( we cannot identify time gap), both the actions are put into the simple past form. 

They reached the hall just before the play began. 

In the sentences like the one written above past perfect form is used with after/long before. Note that the main clause is in the perfect form when long before is in the subordinate clause:

They had reached the hall long  before the play began

Or

The play began after they had reached the hall. 

5. Past perfect is used in conditions clauses to indicate Non-fulfilment of a condition in the past.

If he had gone to Agra he would have seen the Taj Mahal. 

6. Past perfect + infinitive expresses an unfulfilled hope/intention/wish etc... 

I had hoped to win a lottery. ( but I could not)

Past  Perfect Continuous Tense

Form

The past perfect continuous form of a verb is had been + present participle

Uses

1.This tense is used to report an action or event that happened before a point in the past and whose effects are still visible at that point (in the past) 

Prakash had been playing tennis for an hour when the news of selection came in. 

2. It is also used for a repeated action in the past:

The company had been trying to sell out its shares and wind up when the court intervened.