_________ his telephone number. —I have his number, but I _________ tobring my phone book.”

Plants _________carbon dioxide and at the same time _________oxygen. So we may put some in our bedrooms to purify the air.

____ rapid transportation and communication,the whole world seems to be smaller

Generally speaking，the Internet makes________possible for people to get the information they need quickly.

Do you plan to take a vacation this month—Yes, we ________ to Hainan and _______there for five days.