To our disappointment, the trip we had been looking forward to _____ in the pouring rain.
The chairman thought _____ necessary to invite Professor Smith to speak at the meeting.
_____ we were worried about was _______ they could manage to control the pollution.
The manager of the supermarket was so impatient and even rude! I will never go shopping in that supermarket again and __________________.
English is a subject ___________ we should attach great importance.
There are many ways in which you can improve your study. But __________, you should work hard.