Which verb form is used to indicate the progressive tense? verb + -ed
be + verb + -ing
have + been + verb + -ing
have + verb + -ed

There are two options that indicate a progressive tense:

be + verb + -ing

have + been + verb + -ing

Explanation:

A progressive tense is used to talk about about an action that is taking place at the moment of speaking, or to indicate that an action lasted or will last a while.

The structure be + verb + -ing can indicate both the Present Continuous/Progressive and the Past Continuous/Progressive. What determines if it is past or present is the verb "to be". Examples:

- He is organizing the pictures.

- He was organizing the pictures.

The structure have + been + verb + -ing can indicate both the Present Perfect Continuous/Progressive or the Past Perfect Continuous/Progressive. Here, what determines if it is past or present is the verb "have". Examples:

- I have been trying to call him since yesterday.

- I had been trying to call him since the day before.

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