Alice says, " You better tell her, " meaning you should tell her, or it would be better that you told her.

爱丽丝说，“你最好告诉她， ”意思是你应该告诉她， 否则你最好告诉她。

But he is, beyond all comparison, the most agreeable man I ever saw—and if he becomes really attached to me—I believe it will be better that he should not.

不过在我所看见的人当中，他的确是最可爱的一个，任谁也比不上他；如果他真会爱上我——我相信他还是不要爱上我的好。