1.
Don't be obscene.
别开黄腔，别说下流话。
2.
Nice boys do not use naughty words.
好孩子不说下流话。
3.
They'd be laughing making nasty remarks, and make passes at her.
他们会笑着说下流话, 并对她非礼。
4.
That's a rotten thing to say!
说这样的话，下流！
5.
The jokes he told were quite off colour.
他说的笑话很下流。
6.
Using abusive or obscene language.
说话下流的用骂人的或下流的语言的
7.
He addressed me forcibly in the vernacular.
他用下流话对我不客气地说话。
8.
I never heard of such bad taste.
我从没听说过这么下流的话！
9.
His language won't bear repeating, eg because it's too obscene.
他的话别人实在说不出口（如因太下 流）.
10.
Be quiet ! We don' t want to hear that kind of dirt !
别说了! 我们不想听那种下流话!
11.
His comments are not repeatable,eg because they were rude, obscene, etc.
他的话别人实在说不出口（如因粗俗、 下流等）.
12.
dirty book, joke, etc
下流的书、 笑话等
13.
she was sufficiently fluent in Mandarin.
她普通话说得十分流利。
14.
unable to speak freely and easily.
不能流畅、容易的说话。
15.
"History become legend, legend become myth..."
"历史流传成了传说,传说流传成了神话.."
16.
In other words, there is a horizontal flow from evenj point of the ocean towards the points directly under or directly opposite the moon.
换句话说，海水从海洋各处水平流向月球下面的点或背向月球的点。
17.
a vulgar gesture,suggestion, joke
下流的手势、 示意、 笑话.
18.
This is a broad joke.
这是一个下流的笑话。