The price system is a complex network composed of the prices of all the products bought and sold in the economy as well as of a great number of services.
A. the one B. that C. ones D. those
I ______ tell you with certainty that he won’t be able to finish it before the deadline.
A. will B. must C. can D. may
His humorous closing speech was a welcome addition to the ______dull meeting．
A．therefore B．meanwhile C．otherwise D．nevertheless
Someone _______ his car in front of my house and it is blocking my driveway.
A. had parked B. was parking C. parked D. has parked
Many people can’t learn any lessons from the mistakes they’ve made _____they get hurt somehow.
A. whether B. unless C. if D. as
The performance will be given next week. You can go to the student union ______ tickets.
A. for B. with C. by D. on
