Some amazing people _______ our world for the better in the past 100 years.
A．change B．are changing C．have changed D．had changed
_______ was a struggle for me to remember all the strange faces and new names.
A．It B．That C．There D．This
Mountain climbing _______ be tiring and many people feel sick as the atmosphere gets thinner.
A．need B．can C．must D．would
Now she is considering taking some weight-loss pills, _______ she thinks will help her become slim.
A．which B．that C．what D．who
The _______ boy made the police and his family _______.
A．gone; puzzled B．missing; puzzled
C．missing; puzzling D．lost; puzzling
_______ his studies, he started travelling in China.
A．As soon as finish B．As soon as finishing
C．Upon finishing D．Upon finish
