In order to do sth 是表目的,意思是为了做某事,而to do 放句首这一类的语法你可以归纳到动词的不同形式放句首有什么区别. to do 带有为了什么而怎样的意思, to learn english well,you should read more english magazines 而doing 放句首有动名词的意思. learning english well is difficult 而done 放句首是表被动, do 放句首一般是祈使句. having done 放句首是指前半句对后半句造成影响. 还有什么不懂可以追问.
