We use the past continuous to describe an interrupted activity which continued for a period in the past and to talk about things happening for a continuous period in the past.

to say that somebody was in the middle of doing something

He was playing computer games.

for two things happening at the same time

He was playing computer games while she was watching TV.

for things you were in the middle of doing when another thing happened

He was watching TV when Tom arrived.

We form the past continuous tense with the helping verb was/were + present participle (V1 + -ing).

I was going we were going

You were going you were going

He was going they were going

She was going

It was going

We form questions by using the helping verb was/were + subject + present participle

(V1 + -ing).

Was I going? Were we going?

Were you going? Were you going?

Was he going? Were they going?

Was she going?

Was it going?

We form the negative with the helping verb was/were + not + present participle (V1 + -ing).

I was not going we were not going

You were not going you were not going

He was not going they were not going

She was not going

It was not going