现在完成时的句子

I have had lunch just now

The qHow long have you learnt English？你学习英语多久了？
How long have you been learning English？（译文同上。）
He has slept for ten hours．他已经睡了十个小时了。
He has been sleeping for ten hours．（译文同上。）
It has snowed for a long time．雪下了好长时间了。
It has been snowing for a long time．（译文同上。）
They’ve always had a big garden．他们一直有一座大花园。
How long have you known that？你知道这事多久了？
He’s been in hospital since his accident．
I’ve written six letters since breakfast．早饭后我已经写了六封信。
I’ve been writing letters since breakfast．早饭后我一直在写信。
I have knocked five times．I don’t think anyone’s in．
我敲了五次门。我想屋里没有人。
I’ve been knocking．I don’t think anybody’s in．
我一直在敲门。我想屋里没有人。

1.I have answered the quesion .
2.The quesipn has been solved .
3.Computer has been invited for many years.
4.Have you been to the USA?
5.He has gone to home.
6.My mother has been to Canada.
7.Sally has just moved to our town.
8.I have studied English for 10years.
9.Our schoold has been built since 1864.
10.Your sister has gone to USA