帮忙分析2道语法题

judyzou

又要麻烦大侠了, 真不好意思......请大侠帮忙:

1) By focusing on the interesting,(        ) the significant , the penny press newpapers of the 1830's helped to chang the concept of news.
a)which does not necessarily     b)not necessarily       c)was not necessarily             d)nor necessarily being
根据选项空格处只能用not necessarily, 但又不知道这是什么句型?此处省略了什么东西?

2)Areas of fertile soil called deltas, usually (    ) are formed by mud deposited at the mouth of river
a) triangular in sharp b) their shape is triangular c) they have a triangular shape
d) triangular shape
答案是A,但不知道D为什么不对,这里省略了什么成分

braveMBA

1、not necessarily focusing on the significant

2、Areas of fertile soil called deltas，usually triangular in shapE ，are formed by
usually triangular in shapE 修饰 deltas，句子主语是 Areas of fertile soil 。D不符合习惯用法。