飞机杂志广告:have to 和 need to 的区别

have to 和 need to 的区别 have gone to和have been to的区别是什么？ have been to 和have gone to 的区别 need to do和need doing的区别 have to do 和have doing的区别 have to do 和have doing的区别 have been in 和have been to 的区别 We have no need to be afraid of them. have been to和have gone to 的区别和用法！ have to和must有什么区别？have to的否定形式是什么？