____ has helped to protect the environment is worth praising.
A. Who B. The one
C. Anyone D. Whoever
—Why didn’t Tom go to the concert last night ?
— I have no idea,but I think he _____ in his study.
A. read B. have read
C. was reading D. would read
Being examined twice a year is the rule that every driver _____ obey in this city.
A. shall B. can
C. ought to D. need
I’m calling to ask for information about the position____ in the local TV news.
A. advertising B. advertised
C. having advertised D. to advertise
It has been proved ____ several new kinds of medicine____ a positive effect on the cure of H7N9.
A. which,has B. if, has
C. that, have D. what, have
It was the middle of the night_____ my father woke me up and told me to watch the football game.
A.that B.as
C.which D.when