the command grep -i -E '(\b(of|the)\W+){2,}' test.txt produces

命令grep-i-E'(\b(of|the)\W+){2,}'test.txt将生成

youdao

W. E. B. Du Bois's mother was a domestic worker and his father was a barber.

杜博斯的母亲是一位佣人，而他的父亲是一位理发师。

youdao

My opponent so conveniently chose to ignore the fact that W. E. B. DuBois is the first Negroto receive a Ph. D from a white college called Harvard.

对方辩友很巧妙的回避了一个事实，杜博斯正是第一位从一所名叫“哈佛”的白人大学拿到博士学位的黑人。

youdao

My opponent so conveniently chose to ignore the fact that W. E. B. DuBois is the first Negroto receive a Ph. D from a white college called Harvard.

对方辩友很巧妙的回避了一个事实，杜博斯正是第一位从一所名叫“哈佛”的白人大学拿到博士学位的黑人。

youdao