听第3段独白，回答第16-20小题．
16．What day was it yesterday？

C

C

A．Friday．
B．Saturday．
C．Sunday．
17．How long did Betty and Helen wait for the bus？

B

B

A．For fifteen minutes．
B．For half an hour．
C．For an hour．
18．How did they go to the shop at last？

C

C

A．By bike．
B．By car．
C．On foot．
19．What did Betty advise Helen to buy for her grandpa？

B

B

A．A tie．
B．A radio．
C．A shirt．
20．What happened when they got to the shop？

A

A

A．The shop was closed．
B．It began to rain．
C．The things in the shop were sold out．