I do't know how to improve my english ,do you have any good suggestion of courseyou could tell how to learn.thanks

i don't know how to do it句型转换i don't know[ ][ ][ ]do. i don't know ()to do.填what还是how I r_____don't know how to do it.填什么? I don’t know what to do.I don’t know how to do.（ × ） 第二句 how 怎么错了?I don’t know what to do.(正确) I don’t know how to do.（ × ） I didn't know how to do? I didn't know what to do? I didn't know that I do?这三句有什么区别啊? I do not know how to do I am unhappy,i don't know how to do?i want to leave here. i dont know what to do (next) 和i dont know how to do (next)的区别 I didn't know what to do 与I didn't know how to do有什么区别 为什么I don't know what to do成立而I don't know how to do不成立 I don't know how to say it in english How to do i don't know how to do it为什么how后要有一个to I don't know how to say it in english How to do Sure.I know how to do that. I do not know how to i don't know how to do next还是what to do next I don't know how to i don't know how to