This parameter determines the number of threads used to copy map outputs to the reducer, 5 by default.

这个参数决定把 map 输出复制到 reduce 所使用的线程数量，默认值是 5。

youdao

Copy these lists into a map with each list entry identified by the first word (the key) of the list.

将这些列表复制到一个映射且使用列表的第一个单词(键)标识每个列表条目。

youdao

The clerk had a map - but only one copy; he couldn't give it to me.

那里的工作人员有一个地图-可是只有一份；他不能把地图给我。

youdao

The Beatus map of 1109, a copy of one from 776, includes such a continent beyond the Red Sea.

ECONOMIST: Modern man knows where he stands. His map tells him

What kinds of news organizations tend to be big, have lots of writers and bureaus all over the map, use formal language with high standards of copy editing, and have been around long enough to have established reputations?

FORBES: Why Publishers Need to Stop Worrying and Learn to Love Google