It was ______ to go down the hills.

When I heard about the marriage of Andy Lau, you could have knocked me down with a _______ .

Every weekend my younger brother will go to help the old man far away my house,for which he often received some            from the old man,such as a pencil and some sugar.

—Where did you spend last weekend?—At______.

The traditional approach __________ with complex problems is to break them down into smaller，more easily managed problems.