________ super hurricane of Sandy, sweeping across the USA and many parts of America, has up to now caused ________ loss of over 50 billion dollars to the USA alone.
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.
There are 51 students in Class Three, _____ failed in the test.
______ happened to be no one in that house when the typhoon hit the area.