Work in pairs/threes/fours/fives.
Work in groups of two/three/four.
I want you to form groups.
Form groups of three.
Here are some tasks for you to work on in groups of four.
There are too many in this group.
Can you join the other group?
Only three people in each group.
I asked for four people to a group.
Have you finished?
Do the next activity.
Move on to the next activity.
Ask other people in the group.
Ask others in the class.
Interview someone else.
Ask everyone in the class.
Stand up and find another partner.