So we don't know how well TwHF extract works over the long term, and we don't know whether it's safe.

因此，我们不知道长期使用雷公藤所起的作用有多好，也不知道它是否安全。

youdao

But in fact, we know very little about the effects of breastfeeding at long durations, because so few women breastfeed for more than a few weeks.

但实际上，在很长一段时间内我们对母乳喂养的影响知之甚少，因为很少有母亲用母乳喂养超过几周的。

youdao

We've talked about progress long enough; it's now time to apply what we know, so we may grow.

我们已经谈论进步够久了；现在是应用我们所知的时候了，这样我们就会成长。

youdao

you know. We work hard, so we work long hours, and

我们工作繁忙，所以我们工作时间很长，而且，

中央公园的时光 - SpeakingMax英语口语达人

In some quarters free expression online could become a tradeoff: Say anything you like, so long as we know who really is saying it.

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