______ is often the case, we have worked out the production plan.
| A.Which | B.As | C.It | D.What | 
After _________ seemed like hours, a nurse wheeled Doris out of the emergency room.
| A.that | B.there | C.which | D.what | 
---I am going to the supermarket to buy a quilt.
  --- ________ You can easily buy one on the Internet.
| A.Why not? | B.Good idea! | C.Why bother? | D.By no means. | 
The doctor persuaded him to _____ smoking.
  A throw away B put out C give up D take away
That boy spent much time _____ computer games.
  A play B playing C played D to play
I am too tired. I _____ my homework all morning.
  A have been doing B did C do D have done