1.
Our classroom is five meters in length and 3 meters in height.
一般不用long形容房间长短.
二楼hight用的不对, 应该用height 形容高度.
2. He had never heard of such a strange thing before.
before 用来强调之前, 代表从来 都没有听过
3. 不能用we planted, 因为我们城市里的花树并不是我们种的对吧.
所以应该是类似这样的:
We were delighted (强调高兴)to find out lots of trees and flowers had been planted in our city last year.
(大概是 我们很高兴的发现了很多树和花都被种在我们城市了)
我觉得这样更恰当,因为原句没有给谁种的
4. Driving will result in/ cause more air pollution, therefore, we should encourage cycling or walking to work and school.
will xxx 就是被冻结构.
一般不说biking.biking大多指运动项目,cycling比较普遍
5.I am against caging animals, because for animals, it is unsuitable to live in cages.
caging 就是放在笼子里的动词,这样比较简练.