IV.Open the brackets In IVotutnl Porfocl Continuous or in Past Perfect Continuous:
1.1____________ (to learn ) Spanish since December.
2.John_____________ (to smoke) for 20 years when hefinally gave it up.
3.Hello Jack! How long you____________ (to wait) for me?
4.When I arrived, Ann_____________ (to wait) for me.
5.Your child is so dirty! What he________________ (to do)?
6.This student_______________ (to write) a composition fortwo hours before his parents came.