根据括号内的要求改写句子。

1. I don't know what I shall do. (同义句)

    I don't know ___________ ____________ ___________.

2. Cycling is exciting. Skiing is exciting too. (合并成一句)

    Cycling is ___________ ___________ ___________ skiing.

3. There isn't anything else in the fridge. (同义句)

    There is ___________ ___________ in the fridge.

4. Peter is 1.70 meters tall. Mike is 1.68 meters tall. (合并成一句)

    _____________________________________________________

5. Tom is smart, almost 1.75 metres. (对画线部分提问)

    _____________________________________________________