What were you doing when I phoned you yesterday evening？
I _______ my homework．（ ）
A．was doingB．have doneC．did
There is more space in the high﹣speed train and the journey becomes more ．（ ）
A．seriousB．boring
C．dangerousD．comfortable
﹣Would you mind handing me a pair of serving chopsticks？
﹣ ． Here you are．（ ）
A．Of course notB．Yes， I'd love to
C．I don't agreeD．That's all right
﹣Sorry， I took the wrong seat．
﹣____． I will take yours instead．（ ）
A．No wayB．Better not
C．Excuse meD．That's all right
Our business won't improve ____ we offer better service to our customers．（ ）
A．becauseB．unlessC．afterD．since
I came to school ____ this morning because it was my turn to clean our classroom．（ ）
A．earlyB．slowlyC．quietlyD．suddenly