Doing sports is good for your health, _______ ?
When he saw a wallet on the ground, he ________at once.
The train was late, ______ we had to wait for half an hour.
After a long walk, the old man ___________be tired now.
—Which one do you _________, Jim? — I don’t mind. Either will be OK.
—What kind of music does your sister like best? —The one that she can _________. As you know, she likes dancing very much.