13.听第3段独白,回答第16-20小题. 16.What day was it yesterday? A.Friday. B.Saturday. C.Sunday. 17.How long did Betty and Helen wait for the bus? A.For fifteen minutes. B.For half an hour. C.For an hour. 18.How did they go to the shop at last? A.By bike. B.By car. C.On foot. 19.What did Betty advise Helen to buy for her grandpa? A.A tie. B.A radio. C.A shirt. 20.What happened when they got to the shop? A.The shop was closed. B.It began to rain. C.The things in the shop were sold out.