Use the past tense

What were you doing when the phone ...... (ring)?

What were you doing when the phone rang?

I .......... (watch) tv

Was Jane busy when you went to see her?

Yes, she .... (study)

What ..... (the post/arrive) ... this morning?

When did the post arrive this morning?

It arrived while I ... (have) breakfast

Was Tracey at her work today?

No, she .... (not/go) to work

How ....... (break/you) the window?

How did you break the window?

We ... (play) football and it was my turn to kick the ball

We were playing football and when I ...... the ball I hit the window

What .... (you/do) at 5 o'clock this morning? I was asleep