Question

英语问题：什么时候该用过去式，什么时候用现在完成时，什么时候又用过去完成时呢？

过去式的example:(i did....)
现在完成时的example:(i heve been....)
过去完成时的example:(i had been....)
explain them and give me some examples.
第一层的，我还是不明白，可以再详细解释一下吗？（不是要你把那段话改成中文）

Answer 1

if you want to say a completed action in the past, or a habit in the past, you use simple past.eg.I saw a snake yesterday. I was good at maths when i was a child.

if something happened before another action in the past, you use past perfect. eg. I had bought a magzine before i got on the train.

if an action happened at an unspecified time before now, and the action cause some change or result ,you use present perfect.
eg. I have met him before.(so I know him.)
my French has improved since I came to France.(from poor to skillful.)
呵呵,三楼说的有道理,其实我各人觉得时态并不是很难的东西,只是要掌握它必须在初学时看到一个句子就想想为什么作者用这个时态,想多了,自然就理解了.另外在赌局子时一定要注意该句子所发生的时间.

Answer 2

百度知道分别输入：过去式，现在完成时，过去完成时
你会得到非常详细的答案，有很多例句能帮你深刻了解这些烦人的时态，真的！

Answer 3

强调动作在过去某时发生，往往用过去时；
强调过去某时发生而一直延续到现在的动作或状态；
强调动作或状态发生在过去某一动作或时间之前。

Answer 4

苏格兰