You must have been caught in the traffic jam yesterday, ______you?
| A.weren’t | B.didn’t | C.mustn’t | D.haven’t | 
— There are so many current styles, which one should I choose?
  — ________.
| A.It’s your opinion | B.I don’t mind | 
| C.It’s all up to you | D.That’ s your decision | 
________ reducing pullution, man should pay more attention to conserving energy.
| A.As well as | B.As long as | C.As far as | D.as soon as | 
I was too busy at that time, ________ I would have given you a hand.
| A.even though | B.so | C.otherwise | D.nevertheless | 
The question occurred to me ______ we were to get the machine needed.
| A.that | B.what | C.why | D.where | 
— Was her concert a great success?
  — Sure. _______ such a good chance, how could she let it slip away?
| A.Having given | B.Giving | 
| C.Having been given | D.Being given |