If you want to do the experiment again, you had better be more careful_______ you made a mistake.
We must keep our room clean. Dirt and disease go _____ you know.
I tried hard to get some information about the new technology out of his mouth, but he remained____________.
--Could I use your bike, Jack? --Of course, you____________.
When I tried to find _________that prevented so many people from taking part in the program, it seemed to me that there were two main reasons.
--____________? --He is tall and strong.