老师好！
The pilot circled the balloon, under whichthere was a basket containing three men, one of whom was holding a pair of binoculars.
As two of the men were Members of Parliament and the other was the Commanding Officer, the police could not arrest anyone.
第一句句中 whichthere was a basket containing three men 我觉得是 under 后接的是宾语从句（介宾结构），对吗？
第二句中two of the men怎么样理解？是指的一些人中的2个人吗？
期待老师解惑，感谢！
The pilot circled the balloon, under whichthere was a basket containing three men, one of whom was holding a pair of binoculars.
飞行员绕着气球飞行。气球下方有个篮子，篮子里有三个人，其中一人拿着一副望远镜。
As two of the men were Members of Parliament and the other was the Commanding Officer, the police could not arrest anyone.
因为三人中有两人国会议员，另一个是指挥官，因此警察没办法逮捕他们中任何一个人。
第一句句中 whichthere was a basket containing three men 我觉得是 under 后接的是宾语从句（介宾结构），对吗？
不对。这是一个非限制性定语从句，关系代词指代the balloon, 并在从句中作介词which的宾语，介词短语为宾语从句的地址状语。
第二句中two of the men怎么样理解？是指的一些人中的2个人吗？
这一句显然和上一句衔接。the men为特指复数名词，是前文提到过的那些人。即热气球里的三个人。two of the men意为这三人中的二个人，后面的the other即剩下的那个人，即第三个人。总共三个人。即便没前一句，依据the other也可以推出the men的人数为三人。