In mining, efficiency and environmental care must go hand in hand.

千丈长堤，可能因为蝼蚁的洞穴而溃决；百尺高楼，可能因为烟囱的缝隙冒烟而焚毁。

To understand the meaning of a sentence， we must consider the speaker's intention and the context of the utterance.

我对成为名人没有兴趣。我对成为演员感兴趣。

为明天做的最好准备就是今天做到最好。