1.  Uses of Past Simple Tense

We use the Past Simple Tense for the following:

A) To indicate an action that happened in the past. It often takes adverbs/adverb phrases of past time like ‘Yesterday, Yesterday morning, The day before yesterday, The other day, Last night, Ago, In March 2002, etc.’. If the hearer already knows when something happened or can understand this from the context, we can avoid these time expressions; e.g.

i) I did not go to school yesterday. (YESTERDAY: adverb of past time)
ii) Mohan saw Rita two years ago. (TWO YEARS AGO: adverb phrase)
iii) The rabbit just appeared in my garden one day last week. (ONE DAY LAST WEEK: adverb phrase)
iv) She learnt Hindi in Chandigarh. (without adverb of time)
v) I bought this pant in Japan. (without adverb of time)
vi) Sumit decided to continue the course, even though it was proving very difficult.

B) For situations that existed for a period of time in the past, but not now; e.g.

When I was younger I played tennis for my local team.

C) We also use the simple past tense for past habits. We generally use these words to express a past habit: ‘Always, Usually, Daily, Everyday, Never, Often, Rarely, Seldom, Scarcely, etc.’, etc.; e.g.

i) He studied many hours every day.
ii) He always carried an umbrella.
iii) She always came late.
iv) She never missed good plays.

NOTE: Past habits are also expressed by USED TO and WOULD; e.g.

a) I used to smoke in my childhood.
b) He would wait for her outside the school.

C) To express present unfulfilled wishes/desires or unreal situations. In such a case we use this tense with ‘As if, As though, If only, I wish, etc.’. In such a structure if the verb BE (is, am, are, was, etc.) is to be used, we use WERE for all persons, numbers; e.g.

i) I wish I were the President of India.
ii) He speaks as if he were the chairman of this company.
iii) If I became the P. M. of India, I would eradicate unemployment totally.
iv) He boasts as if he knew everything about Delhi.

NOTE-I: But if it’s a past unfulfilled wish/desire or unreal situation we use the past perfect tense with the above expressions; e.g.

a) She talks to me as if she had come from heaven.
b) He speaks as though if he had conquered the world.

NOTE-II: IF, AS IF, AS THOUGH can take the present tense also when it’s not a pure imagination/wish; rather there are chances of fulfillment of such a wish; e.g.

The President of the AAM party said, “If I become the Prime Minister I will eradicate corruption totally.”

D) We use the past simple tense with ‘It is time, It is high time, It is opportune time, It is about time’ to express that the correct/right time for something has passed i.e. it’s a little late to do something. When such is the idea we use a clause i.e. SUBJECT + VERB after these expressions; e.g.

It is time we left.

[Here the past ‘LEFT’ is correct. It means we are a little late to leave; we should have left by now.) Sometimes the word HIGH or ABOUT is added to emphasize the idea. This sentence can be expressed like this also (If we want to emphasize):  It’s high time we left. OR It’s about time we left.]

NOTE-I: Though the clause after IT IS TIME takes the verb in the past subjunctive, if the subject of that clause is I, HE, SHE, or IT the verb is WAS; not WERE; e.g.

It’s time I was going.

NOTE-II: IT IS TIME can be followed by the infinitive (TO + V1); like in ‘It’s time to start; OR by ‘for + object + infinitive’; like in It’s time for us to start. In both these uses we mean ‘Correct time has arrived to do something.’; e.g.

a) It is time to open the shop.
b) It is time for me to leave for the station.

E) When two events happened in the past, we use the Past Perfect Tense for the event that took place first and the Past Simple Tense for the event that occurred second; e.g.

i) The bell had rung before I reached school.
ii) The teacher had entered the class before the students took their seats.

Past Simple Tense V/s Present Perfect Tense

1. When we talk about something that happened in a period of time up to the present we use the Present Perfect Tense, but we use the Past Simple Tense to talk about something that happened at a particular finished time in the past; e.g.

#-a) Science has made many major advances this century.
b) Science made many fundamental discoveries in the 18th century.

#) I threw away most of my books when I moved house.

2. To talk about states we can use both the present perfect and the past simple. If we talk about a state that existed in the past and still exists now, we use the present perfect; and if the state no longer exists we use the past simple; e.g.

a) I knew him when we were both working in Chandigarh.
b) I have known him most of my working life. (means ‘I’m still working.’)

3. Time adverbs referring to the present, such as TODAY, THIS MORNING, etc. can also be used with either of the Present Perfect Tense and Past Simple Tense. If we see the time as a past, completed period of time, we use the past simple; but if we see the time as a period including the present moment, we use the present perfect; e.g.

1-a) I didn’t shave today. (means the usual time to do shaving has passed and suggests I will not shave today.)
b) I haven’t shaved today. (means TODAY is not finished and suggests I may shave later.)

2-a) I wrote this letter this morning. (means The morning is over.)
b) I’ve written this letter this morning. (means It is still morning.)

2. Uses of Past Continuous Tense

A) To denote an action that was going on at some time in the past; e.g.

i) They were staying with me at the time of the robbery,
ii) It was raining in the morning.
iii) It was getting darker.

NOTE: We don’t normally use the past continuous with certain verbs describing states; e.g.

The house belonged to me. (not ‘The house was belonging to me.’)

B) The Past Continuous Tense is used with the Past Simple Tense when a new action happened in the middle of a longer action. The Past Simple is used for the new action and the Past Continuous is used for the longer action; e.g.

i) The light went out while I was reading.
ii) When I saw him he was playing cards.
iii) During the time I started to get chest pain, I was playing badminton a lot.

C) For continued past habits; then we use the words ALWAYS, CONTINUALLY, etc.

He was always grumbling.

3. Uses of Past Perfect Tense

A) For an action completed before a certain point in the past; e.g.

i) I met him in Mumbai in 2001. I had seen him last six years before.
ii) The house had been empty for several months.
iii) I had never met you before yesterday.

Deepa felt very pleased with herself. She had found what she was looking for.

[Here FOUND instead of HAD FOUND will be incorrect as it’s an action completed before a certain point in the past. That past point here is ‘The moment Deepa felt pleased with e’.’]

INCORRECT: I was just about to leave when I had remembered my purse.
CORRECT: I was just about to leave when I remembered my purse.

[The past perfect here will be wrong as there is no point of the past here before which the event ‘Remembrance of the purse’ occurred. ‘I was just about to leave’ is just a past expression.]

INCORRECT: Jugal told me that I passed the examination.
CORRECT: Jugal told me that I had passed the examination.

INCORRECT: She didn’t expect to see Rahul again, so she was delighted when they met at the airport.
CORRECT: She hadn’t expected to see Rahul again, so she was delighted when they met at the airport.

INCORRECT: When Ruchi checked that children were asleep, she went out to the cinema.
CORRECT: When Ruchi had checked that children were asleep, she went out to the cinema.

B) When two events happened in the past with a certain gap, we use the past perfect for the first event and the past simple for the second; e.g.

i) When the doctor arrived the patient had died.
ii) She had done her homework when Mohan came to see her.
iii) The judge convicted him after he had heard the case.

[But if there is no gap between the activities, means they happen immediately after one another, we use the past simple in both the clauses. We also use the past simple in both the clauses when the second event is the result of the first.]

Compare:

1-a) When Varun stopped laughing, Shweta left. (Means ‘Shweta left just after Varun stopped laughing.’)
b) When Varun stopped laughing, Shweta had left. (Means ‘Shweta had already left.’)

2-a) I got up when the phone rang. (Means ‘The phone rang immediately after I got up.’)
b) I had woke up when the phone rang. (Means ‘I had already got up.’)

C) With ALREADY and JUST the Present Perfect Tense or the Past Perfect Tense is used; not the Past Simple; e.g.

i) The film had already begun by the time we got to the cinema.
ii) She had just entered her room when the phone rang.
iii) I’ve just decided to sell my apartment.
iv) The train has already left.
v) I’m on my way to the station. Their train has just arrived.

D) We use the past perfect tense with the verbs HOPE, EXPECT, MEAN, THINK, INTEND, SUPPOSE, WANT when they are used to express that a past hope/desire was not fulfilled; e.g.

i) I had thought that I would succeed.
ii) I had wanted to see you but I fell ill.

NOTE: But if the above verbs are in the simple past tense, it means the hope/desire was fulfilled; e.g.

a) I thought that I would succeed.
b) I wanted to see you.

E) To express past unfulfilled wishes/desires or unreal situations. In such a case we use this tense with AS IF, AS THOUGH, IF ONLY, I WISH, etc.; e.g.

i) She talks to me as if she had come from heaven.
ii) He speaks as though if he had conquered the world.
iii) Raman behaves as if he had returned from Australia.

NOTE: But if it’s a present unfulfilled wish/desire or unreal situation we use the Past Simple Tense with the above expressions; e.g.

a) I wish I were the President of India.
b) He speaks as if he were the chairman of this company.
c) If I became the P. M. of India, I would eradicate unemployment totally.
d) He boasts as if he knew everything about Delhi.

4. Uses of Past Perfect Continuous Tense

We use this tense for an action that began before a certain point in the past and was continued up to that time; e.g.

i) When Rajat came to see me, I had been taking my playing cards with my brother for 10 minutes.
ii) The teacher had been teaching for an hour when I went to see him.
iii) They had been expecting the news for some time.

Past Perfect Continuous Tense V/s Past Continuous Tense

We use the Past Perfect Continuous Tense for finished continuing actions in the past but we use the Past Continuous Tense for the actions that were still in continuation in the past, e.g.

1-a) When we met Rohit, he had been reading the newspaper. (Means ‘He had finished reading the newspaper.’)
b) When we met Rohit, he was reading the newspaper. (Means ‘He was in the middle of reading the newspaper.’)

2-a) When she got home, water had been leaking through the roof. (Means ‘Water was no longer leaking.’)
b) When she got home, water was leaking through the roof. (Means ‘Water was leaking still.’)