There will not be enough space to _____ the earth in the future. [ ]

Could you tell me ______ ? —Glad to help.

Internet is an important _____ for people to get the latest news.

____ a cold winter morning, I met her in the street. [ ]

Shanghai is the city ______ the 2010 world Expo is held. –So it is a city____ most of us want to vist this summer.