发电机定子绝缘测量条件？

No one knows how man learned to make words. Perhaps he began by making sounds like those made by animals. Perhraps he grunted like a pig when he lifted something heavy. Perhaps he made sounds like those he heard all around him water splashing, bees humming, a stone falling to the ground. Somehow he learned to make words. As the centuries went by, he made more and more new words. This is what we mean by language.
People living in different countries made different kinds of words. Today there are about fifteen hundred different languages in the world. Each contains many thousands of words. A very large English dictionary for example, contains four or five hundred thousand words. But we do not need all these. Before you leave school, you will learn only a few thousand of them.

In order to make a speech, we need sounds and words.

A. Right.

B. Wrong.

C. Doesn’t say.