American English has so many because the American people have come from all over the worl

问题补充：

American English has so many because the American people have come from all over the world.

A. grammar

B. vocabulary

C. pronunciations

D. dialects

答案：

A. grammar

B. vocabulary

C. pronunciations

(答案→)D. dialects

解析：句意：美国英语有这么多的方言，因为美国人来自世界各地。grammar语法；vocabulary词汇；pronunciations发音；dialects方言。结合后半部分的理解，美国人来自五湖四海，所以说英语难免不带有家乡味。所以最佳选D。

考点: 考查名词的用法。