在于

1. 与其说成功在于运气不如说是辛勤努力。
   Success lies not so much as in luck as in hard work.
2. 机智在于知道自己可以过分到什么程度。
   Tact consists in knowing how far we may go too far.
3. 该计划的妙处在于简洁明了。
   The beauty of the plan consists in its simplicity.
4. 抽税的本领在于：从鹅身上拔下最大限度的毛，而只让它发出最低限度的嘶嘶声。
   The art of taxation consists in so plucking the goose as to obtain the largest amount of feathers with the least amount of hissing.

在的英语翻译：

于的英语翻译：