The astonishing similarity between my brother and my first-born son. [+ between]

我弟弟和我的大儿子长得惊人地相似

There was a very basic similarity in our philosophy.

我们的人生哲学在根本上很相似。

She is also 25 and a native of Birmingham, but the similarity ends there.

她也是 25 岁，也是伯明翰本地人，但也就这么多相似点了。

There were significant similarities between mother and son. [+ between]

母子之间有很多相像的地方。

The similarities between Mars and Earth were enough to keep alive hopes of some form of Martian life.

火星和地球之间的诸多相似处足以让人们对火星上存在某种生物抱以希望。