The gap between rural and urban education in China is widening, and education is the key to _____ rural problems.
____ 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.
________, as long as I’m with nature, I don’t care.