When did you return to Nanjing last Friday?—It was not until midnight _______ it was snowing heavily.[ ]

What does your brother -He is of medium build.

________ the tower building，where you can see the whole city

______ he realized it was too late to retum home.[ ]

Nothing is so easy as ________ parents to raise their expectations of their children too high(2012·福建，33)