Most young people are interested in pop music , _____Jack shows great interest in classical music[ ]

I _________ think there _________ be more buildings in two years.

With Shanghai World Expo drawing near, volunteers are making use of every minute to ____ their foreign language because language volunteers must pass a written test and an interview.

How long has the nationwide ban(禁止) on plastic bags been put into practice—__________ the beginning of June.

How often are the Olympic Games held —_____four years.