改错(共5小题，每小题2分，共10分)

小题1:That is amazing that such an old man can climb a 1000-meter-high mountain.

小题2:On the another hand, the Chinese paintings will take a longer time to learn than oil paintings.

小题3:If I am you, I would work in a small mountain village.

小题4:Once you get into trouble, don’t be nervous; that is, take easy.

小题5: After being ill for 10 days, Mary is finally back on her foot again.

在潮湿而且触电危险性大的环境进行电焊时，安全电压应为（）V。