Have you ever practiced conversations with friends_____(improve)your speaking skills?请问为什么不能填improving而是填to improve?

造句：Have you ever. Have you ever heard Have you ever have you ever与have you ever been的区别 you have ever said before和you have ever said 英语造句have you ever “Have You Ever Seen Me? Have you ever seen snow? have you ever.是什么句型 have you ever fed them? Have you ever had these? Have you ever been employed? Where have you ever been? have you ever [ ] [drink]coke? Have you ever ( ) [study] abroad? have you ever move house have you ever have Italian food? have you ever 和 do you ever 有什么区别?