It's a hard work, so you must work hard.

这是一件艰苦的工作，因此你必须努力去做。

youdao

When you learn your lessons in school, you must work hard and not give up.

当你在学校学习时，你必须努力学习，不要放弃。

youdao

It isn't like a duck to water to learn a foreign language, so you must work hard.

学习一门外语不像鸭子会游泳那么简单，必须努力才行。

youdao

We know we must work with you to do that.

VOA: standard.2009.03.31

Now, I don't know how far back it goes but it must be that in ancient times some people would say, all right you're going to be doing more work or you're contributing more to this enterprise, we'll give you a bigger share of the profits.

我不知道这能追溯到什么时候,但在古时候肯定有人说,好吧,你比别人干得多,你对公司的贡献更大,我们会把收入的大头给你

耶鲁公开课 - 金融市场课程节选

And you assumed that he must work out.

你认为他肯定常常锻炼。

Do you 课堂 - SpeakingMax英语口语达人

President GEORGE W. BUSH: The Supreme Court said you must work with Congress.

NPR: Bush Defends Policy on Detainees, Iraq Strategy

But these states have a Protestant work ethic: we'll help you find a job, they say, but you must work if you can.

ECONOMIST: Charlemagne

Now, you must work backward to solve the loss of that rule-of-thumb: To earn at those same rate today, you will need more stocks and possibly a venture into lower-grade credit.

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