Singular (1)

{blah}ing.

sitting.

standing.

reading.

writing.

sleeping.

eating.

drinking.

watching TV.

looking at the clock.

listening to the teacher.

cooking.

studying.

running.

walking.

I am (not)

You are (not)

He is (not)

She is (not)

It is (not)

Plural (2,3...)

We are (not)

You are (not)

They are (not)