If we don 't know our planet, our future may be in danger.

要是我们不知道我们的星球，我们的未来就会有危险。

youdao

If we don? T start out now, we must risk missing the train.

如果我们现在不出发，就可能会赶不上火车。

youdao

It is a big loss to us, 'he says.' If we don "t sell, it is only a paper loss." '.

他说，那不是一小笔钱，这对我们来说是很大的损失，只要我们不抛，那就只是纸面上的亏损。

youdao

But it will be if we don't take dramatic action as soon as possible.

VOA: special.2009.01.09

In other words, if we don't have to worry about entropy or volume equilibrium is achieved when energy is at a minimum.

换句话说，如果我们不担心熵,和体积的平衡,那么能量就得是最小的。

麻省理工公开课 - 热力学与动力学课程节选

I think that if we don't address it, it has the potential to have very, very serious effects

我觉得如果我们不解决的话，可能有非常非常严重的后果

全球变暖和发达国家 - SpeakingMax英语口语达人

It's bad business if we don't accept a bid similar to what Sunderland offered.

BBC: SPORT | Football | Everton set to improve Baines bid

And they're going to more than double over the next decade if we don't do anything.

WHITEHOUSE: Help for Homeowners in the Hardest Hit States

We're playing against a worthy opponent and if we don't play well, they beat us.

NPR: Pacers, Heat Prepare For Crucial Game 5