GRAMMAR UNIT 1.

-PAST PERFECT CONTINUOUS.

FORM.

·AFFIRMATIVE.

I/You had been studying.

He/She/It had been studying.

We/You/They had been studying.

 ·NEGATIVE.

I/You had not (hadn't) been studying.

He/She/It had not (hadn't) been studying.

We/You/They had not (hadn't) been studying.

·INTERROGATIVE.

Had I/you been studying?

Had he/she/it been studying?

Had we/you/they been studying?

USES.

An action which continued up to another past action.

EXAMPLES.

They had been studying for two hours before we arrived.

TIME EXPRESSIONS.

For hours, since last April, all morning, when, until, before.