噪声污染源主要有：工业噪声污染源、交通噪声污染源、（）噪声污染源和（）噪声污染源。

Culture is the sum total of all the traditions, customs, belief and ways of life of a given group of human beings. In this sense, every group has a culture, however savage, undeveloped, or uncivilized it may seem to us.
To the professional anthropologist, there is no intrinsic superiority of one culture over another, just as to the professional linguist there is no intrinsic hierarchy among languages.
People once thought of the languages of backward groups as savage, undeveloped form of speech, consisting largely of grunts and groans. While it is possible that language in general began as a series of grunts and groans, it is a fact established by the study of "backward" languages that no spoken tongue answers that description today. Most languages of uncivilized groups are, by our most severe standards, extremely complex, delicate, and ingenious pieces of machinery for the transfer of ideas. They fall behind the western languages not in their sound patterns or grammatical structures, which usually are fully adequate for all language needs, but only in their vocabularies, which reflect the objects and activities known to their speakers. Even in this department, however, two things are to he noted: 1. All languages seem to possess the machinery for vocabulary expansion; either by putting together words already in existence or by borrowing them from other languages and adapting them to their own system. 2. The objects and activities requiring names and distinctions in "backward" languages, while different from ours; are often surprisingly numerous and complicated. A western language distinguishes merely between two degrees of remoteness ("this" and "that"); some languages of the American Indians distinguish between what is close to the speaker, or the person addressed, or remote from both, or out of sight, or in the past, or in the future.
This study of language, in turn, casts a new light upon the claim of the anthropologists that all cultures are to viewed independently, and without ideas of rank or hierarchy.

The example of American Indian languages in the passage is to illustrate that______.

A．American Indian languages are not backward

B．"backward" languages are borrowing from other languages

C．"backward" languages may possess quite complicated vocabularies

D．western languages may also borrow from "backward" languages

积累运用。

1．当你勉励同学要抓紧时间学习时，会引用这样的古代名言：“__________________________。”当有人取得了一点成绩就沾沾自喜时，你会这样奉劝他：“_______________________。”当你的朋友在学习中遇到困难，你会这样鼓励他坚持下去：“______________________________。”

2．在这一单元中，我们认识了________________的少年周恩来，________________的叶圣陶先生，具有__________的乌塔。

招标项目设有标底的，标底应当在（）时公布。

A、公布招标公告

B、发售招标文件

C、开标

D、评标

净选时应去瓤的药物是

A．栀子

B．苍术

C．枳壳

D．黄柏

E．知母

编码器的主要功能是什么？