http://www.englisch-hilfen.de/en/grammar/past_progressive_form.htm

Form of the Past Progressive/Continuous

We use a form of to be (was or were), the infinitive of the verb and the ending –ing.

to be (was, were) + infinitive + -ing


Affirmative sentences:

I/he/she/it was playing football.
We/you/they were playing football.

NOTE: Use was with I, he, she, it –
and were with all other pronouns.

In affirmative sentences we do not use short forms in the Past Progressive.


Negative sentences:

I/he/she/it was not playing football.
We/you/they were not playing football.

We use short forms in the Past Progressive in negative sentences:

I/he/she/it wasn’t playing football.
We/you/they weren’t playing football.


Questions:

In the Past Progressive we put the auxiliary (was or were) before the subject
(Auxiliary – Subject – Verb – Rest). see: Questions in the Past Progressive

Was I/he/she/it playing football?
Were we/you/they playing football?