工作时一定要保持舒适的姿势。

Make sure that you are working in a comfortable position.

《牛津词典》

锻炼时一感到口渴就喝水。

Drink whenever you feel thirsty during exercise.

《柯林斯英汉双解大词典》

你永远说不清她要干什么。她一时一变。

You never know what to expect with her. She's so temperamental.

《牛津词典》

So I'll tend to talk about "the Roman household," because that's what's more meaningful sociologically when we talk about this.

所以我倾向于用“罗马家户“,因为这样说，我们讨论这一问题时,更有社会学意义。

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However, you only use this when the other person has been directly discussing, speaking on a subject.

但是，只有当他人在直接谈论某一话题时，你才能使用这个句型。

It sounds like 课堂 - SpeakingMax英语口语达人

This decision is also hard to make because when you are a backend technology provider, it's like selling a piece of commodity.

之所以这是一个困难的决定还因为,当作为后台技术提供商时，就像出售一件商品似的。

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