It was totally by chance they discovered the entrance to the underground palace.
A．when B．which C．why D．that
The boys by the coach now will take part in the sports meeting of the school next month．
A．chosen B．being chosen
C．choosing D．to be chosen
Schools in the cities are well equipped those in the countryside are poor．
A．if B．while C．so D．as
I received a letter， poor spelling made me think it was written by a child．
A．which B．that C．whose D．who
The new online library makes possible for students to choose books by smart phone off campus．
A．it B．one C．that D．this
We were delayed at the airport．Otherwise，we here by lunch．
A．must have been B．could be
C．should be D．would have been
