[英文]請教一下英文文法!!

Question

請教一下各位先進;
如果:
1. A is separated from B by a distance.
2. The distance is defined between C of A and D of B.
3. The distance is twice of the focal length of B.
請教這三句,可否把他寫成如下:

A is separated from B by a distance, defined between C of A and D of B, that is twice of the focal length of B.

如果不恰當或者是有問題的話,不知有沒有更好的寫法呢?
謝謝!

Answer 1

因為你希望合併三個句子，所以要找尋三者適當的連接位置。而你的合併方法雖然很接近正確，但子句的部分有錯。
關鍵處是在 "the distance"，第一句中的 "the distance" 是受詞，後兩句是對 "the distance" 形容的句子，所以可合併成形容詞子句附加在第一句後面，又兩者地位相同，所以可用 "and" 連接。修改如下：
A is separated from B by a distance that is defined between C of A and D of B and twice of the focal length of B.
當然也有其他的合併方式，但第一句的句型會改變，改變後合併如下：
The distance that is defined between C of A and D of B and twice of the focal length of B separates A from B.

Answer 2

原發問者的寫法是對的