383. Other animals, it is true, communicate with one another by means of cries: for example, many birds utter warning calls at the approach of danger; monkeys utter different cries, such as expressions of anger, fear and pleasure.

英语四级译文:
其他动物通过叫喊声相互沟通，这确有其事：例如，许多鸟在危险临近时发出警告的叫声；猴子发出不同的叫喊声来表示愤怒、恐惧和高兴。

四级词汇讲解:

it is true为插入语。

communicate意为“与……沟通，交流情况”。如:
The police communicate with each other by radio.警察通过无线电相互联络。

by means of意为“以…方式，通过…的手段”。如:
The theory is illustrated by means of Power Point.该理论以 PPT的形式进行讲解。

utter此处意为“发出(声音)”。如:
Why do you utter a sign?你为什么要发出叹气声呢?

at the approach of意为“在……将到的时候”。如:
A bird has to give way at the approach of an elephant.大象走过来，小鸟要让路。