He noticed someone (     ) out of the classroom.

• ran

• running

• to run

I have listened to the singer (     ) for two hours.

• sings

• has sung

• sing

She saw her classmate (     ).

• to punish

• punished

• punishing

We (     ) a bird singing in the tree.

• look

• smell

• watch

I see a boy （ ） in the playground.

• playing

• played

• to play

She watched her children ( ) assignments in her bedroom.

• completed

• complete

• to complete

They felt the materiels ( ) by the worker in the construction site.

• move

• moving

• moved

I heard a baby ( ) in the room.

• crying

• cryed

• cry