He mentioned in the letter that he ______ join us once he ______ our invitation.
| A．would come; received | B．had come; received |
| C．was coming; had received | D．came; received |
______ he referred to in his article was unknown to the general reader.
| A．That | B．What | C．Whether | D．Where |
____ matters most in learning English is enough practice.
| A．What | B．Why | C．Where | D．Which |
I just wonder __________ that makes him so excited.
| A．why it does | B．what he does | C．how it is | D．what it is |
Engines are to machines _________ hearts are to animals.
| A．as | B．that | C．what | D．which |
____ team wins on Saturday will go through to the national championships.
A. No matter what B. No matter which C Whatever D. whichever