—Did you find the missing couple in the mountain yesterday?—No, but we ________ to get in touch with them ever since.
---- Ann is in hospital. ---- Oh, really? I ______ know. I ______ go and visit her.
I was out of town at that time, so I don’t know exactly how it ______.
The number of foreign students attending Chinese universities ______ rising steadily since 1990.
.----Look at the dark clouds outside. please take the umbrella with you. ---
We all feel it is Jack as well as his wife that for their son's bad performance at school.