Tom never dreamt of__a chance for him to be sent abroad soon.A.having B.there being我知道of是介词,后面跟分词形式,那为什么不选A呢!“有一个机会”不是也讲得过去.我分不多,还想问其他题呢,

Tom never dreamt of__a chance for him to be sent abroad soon.A.having B.there being我知道of是介词,后面跟分词形式,那为什么不选A呢!“有一个机会”不是也讲得过去.我分不多,还想问其他题呢,
Tom never dreamt of__a chance for him to be sent abroad soon.A.having B.there being
我知道of是介词,后面跟分词形式,那为什么不选A呢!“有一个机会”不是也讲得过去.我分不多,还想问其他题呢,

Tom never dreamt of__a chance for him to be sent abroad soon.A.having B.there being我知道of是介词,后面跟分词形式,那为什么不选A呢!“有一个机会”不是也讲得过去.我分不多,还想问其他题呢,
of后如果接having a chance后面就不用for him了.
there being a chance for him to be...
本结构的本来是
there was a chance for him to be sent abroad soon
dream of 后不能接that从句,所以就用there being结构（这个其实是动名词的复合结构充当宾语）
None would dream of there being such aplace.
——of的后头本来要接的是“there was such a place.”

如果用having 原句应该为 tom has never dreamt of having a chance to go abroad soon.