—What’s that noise?—Oh, I forgot to tell you. The new machine ________.
After the long-distance running race, we students returned home, ___________.
This is the very plan for our May Day holiday _______ was made by our classmates.
Is _____ necessary to take off our shoes when we enter the computer lab?
____ matters most in learning English is enough practice.
Only whenin the afternoonable to leave.