would do 表过去习惯性的动作,翻译成：（过去）总是会.如：
The old man would sit in front of the house,waiting for his son to come to visit him.
那位老人（过去）总是坐在屋前,等儿子来看他.
used to do 强调过去曾经做过,而现在不做了,如：
There used to be a hospital here,but now there is a beautiful garden instead.
此地过去曾有一家医院,但现在却是被一座漂亮的花园所代替.