Many people have trouble in finding jobs, so that many of them become ______(hope, hopeless) in life.

Most metals ______electricity very well.(conduct , conductor )

Car drivers should always ______their seat-belts. (fast, fasten)

The new maglev train that connects the city of Shanghai with Pudong Airport is both fast and _____ .(comfort, comfortable)

Science is of great help in developing the ______(economy,  economic)

After a whole morning’s sports activities, we need to _____for the rest of the day.(fuel , refuel)

It is necessary to have a physical ____every year. ( examine , examination)

Haven’t I told you many times that you should not eat fruit that is not ____? ( ripe, ripeness)

Junk food may ______great, but it is not good for your health.   (taste, tasty)

The enlarged school campus is _____the old one.

 A. as three times big as                     B. three times as big as

 C. bigger three times than                 D. as big as three times