In general the past tenses are used to talk about something that started and finished at a definite time in the past
The past Simple is the most common of all four, we use simple past to express the idea than an action started and finished at a specific time in the past.
We form the Simple past with regular verbs, and using their infinite forms and adding "ed"
Want ---> Wanted
Watch ---> Watched
Stay ---> Stayed
With verbs that finish with "e" we just add and "d" at the end.
If the verb finish with a short vowel and a consonant(except "y" and "w") we add another consonant and the "ed"
Stop ---> Stopped
Commit ---> Commited
With that finish with a consonant and a "y", must be changed with and "i".
Study ---> Studied
subject + verb
She wanted to dance
Subject + To be + Not
She wasn't a good actress.
To be + Subject...?
Was he a doctor?
Past simple is used to talk about an action that started and ended in the past
Larry worked last night
Is used to a series of actions in the past
He studied for an hour in the morning and then he went to school for his mid-term.
Used with habits
She walked 5 kilometers everyday.
Actions of long duration
She worked in the hospital for many years.
I played piano when i was a child.
Past continous is used when we refer to action that happened in a specific moment in the past.
To form the past continous we use the verb "to be" and the verb finish with "ing".
I, He, She, It ----> Was
You, Were, They ----> Were
Subject + auxiliar verb (to be) + gerund
I was talking
Subject + auxiliar verb (to be) + not + gerund
He was not(wasn´t) eating
Auxiliar verb(to be) + Subject + gerund?
Were you talking?
Past continous is used for a long action that was already interrupted. The action that is interrupted it is in past continous and the action that interrupt the other one is in past simple. "When" and "while" indicate the use of past simple and continous. In general we use past simple after "when" and past continous after "while"
My father called me while i was watching T.V
He was walking to work when he fell
We use past continous to talk about actions in a specific period of time in the past
Paula was studying at 10 o'clock last night
Past continous is used when two actions were happening at the same moment in the past
My dad was fixing his car while i was cleaning my room.
The past perfect is used when we talk about action that happened before others actions in the past.
To form the past perfect we use the auxiliar verb "To have" and the past participle, the auxiliar verb is going to be in past form.
I, You, We, They , She , He , It ----> Had
Subject + Had + past participle
I had studied before i went to school.
Subject + Had + Not + past participle
She had not(hadn't) eaten before the lunch.
Had + Subject + past participle?
Had you studied before the exam?
We use Past Perfect to refer an action that started in the past previous to another action that started in the past.(The action that happened first is in past perfect and the second action is in past simple)
I had read the book before i saw the movie
For action that happened in a specific period of time
I had already woken up when the alarm clock rang
We use Past perfect for actions that started in the past and continue to an specific point in the past
She had only owned one car before she bought a new one.