want过去是有.
我昨天想要去图书馆的.I wanted to go to the library yesterday.这里want相当于plan .我明天准备去图书馆.通常用going to 不会用到want.因为want的本意就是想要怎样怎样,放在将来是很别扭.
need过去时很多,将来时也有,但不多.
但是要注意有两种过去时表述方式：
1.I didn't need his help.
2.I needed that job last year.
将来式：
I will need the tool tomorrow.
希望可以帮助你,有问题给我留言啦：）