15. An awful crash between an express train and a bus _____ , however, occur the other day in Russia.A. does B. did D. has to D. had to
Nowadays, most young people enjoy ______ on the Internet.
The girl often helps her best friend, ______ is not good at English.
–-Tom, ________we go home together this afternoon ? –- Ok !
_______ was at the end of the meeting that Mr. Smith made the decision .
I invited Joe and Linda to the party, and both of _______ came.