You use rather when you are correcting something that you have just said, especially when you are describing a particular situation after saying what it is not.
Twenty million years ago, Idaho was not the arid place it is now. Rather, it was warm and damp, populated by dense primordial forest.
2000万年前,爱达荷州不像现在这样干旱。确切地说,它那时温暖潮湿,到处生长着茂密的原始森林。
You use rather to indicate that something is true to a fairly great extent, especially when you are talking about something unpleasant or undesirable.
I grew up in rather unusual circumstances.
我在相当不寻常的环境中长大。
I'm afraid it's a rather long story.
我恐怕这是个相当长的故事。
You use rather before verbs that introduce your thoughts and feelings, in order to express your opinion politely, especially when a different opinion has been expressed.
I rather think he was telling the truth.
我或多或少地相信他在说真话。
You use rather when you are describing what a particular situation is not like, after saying what it is.
She made students think for themselves, rather than telling them what to think.
她让学生们自己思考,而不是告诉他们思考什么。
rather than
You use rather than when you are contrasting two things or situations. Rather than introduces the thing or situation that is not true or that you do not want.
The problem was psychological rather than physiological.
这是个心理问题而不是生理问题。
would rather
If you say that you would rather do something or you'd rather do it, you mean that you would prefer to do it. If you say that you would rather not do something, you mean that you do not want to do it.
If it's all the same to you, I'd rather work at home.
如果对你来说都一样,我宁愿在家工作。
Kids would rather play than study.
孩子们宁愿玩也不愿学习。