What can we students do _____ the environment?
This educational CD-ROM makes _____ easier for you to learn English.After using it for a month, you’ll have no difficulty ________ with foreigners.
—Can I walk across the road now, Mrs.Chen?—No, you ______.You have to wait until the light turns green.
--- Middle school students hardly know anything about shopping online, __________ they? --- ________.It’s very popular with teenagers.
—Are you happy with your grades in the math exam? ---Not at all.I can’t have _______.
I have a ______ frienD. He has lived in the _____ island for half a year to do some research. A. close; alone B. close; lonely C. closed; alone D. closed; lonely