It was along the Mississippi River _____ Mark Twain spent much of his childhood.

____ computers are of great benefit to the development of science and technology.

estimated that the novel will be_____ of his best sellers, for his novels are quite popular among young people

Mike is only 15 years old. He is not ______ to get a driver’s license(驾照).

There was a big fire in the building last night ____, all the people were able to escape