Cindy shut the door heavily and burst into tears. No one in the office knew（）she was so angry.

单项选择题Bats are surprisingly long-lived creatures, some（）a life span of around 20 years.

A. having
B. had
C. have
D. to have

单项选择题The issue is how to（）of radioactive waste.

A. deal
B. dispose
C. disposal
D. do

单项选择题I'm tired out. I（）all afternoon and I don't seem to have finished anything.

A. shopped
B. have shopped
C. had shopped
D. have been shopping

单项选择题Let's learn to use the problem we are facing（）a stepping-stone to future success.

A. to
B. for
C. as
D. by

单项选择题Experts think that（）recently discovered painting may be（）Picasso.

A.the；不填
B.a；the
C.a；不填
D.the；a