21．____________

How many planes use the airports every day?

19．What happened to the small boy?

A．He couldn't find his father．

B．He couldn't go home．           C．He couldn't find his mother．

18．Where did they go on Tuesday?

A．To the shop．                 B．To the sea．                 C．To the museum．

17．What did they do in the afternoon?

A．They went swimming．         B．They did some shopping．

C．They played football．

16．What was the weather like on Monday?

A．It was cold．                  B．It was rainy．               C．It was sunny．

14．How long did the journey last?

A．About 21 hours．              B．About 12 hours．              C．About 3 hours．

A．13．                       B．14．                     C．15．

13．How many people joined the program?