逗号/逗点在中文或英文里是再普通不过的一个标点符号;可是，它的用法在中文和英文里可就不一定相同了。
成份指：词、短语(phrase)、子句(clause)等。
2.1.1 逗号用在以 and, but, for, nor, or, so, yet 等连接词的两个主要子句
1. My father is fond of fishing, but my mother prefers hiking. (以 ,but 连
2. He painted the exterior of the house, and she painted the interior. (以
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2.2.1 用逗号分开两个以上的并列形容词：(如果并列的形容词之间可加上and,
1. That tall, distinguished, good looking fellow. (可写成 He is a tall and
2.She is a little and old lady. (不可写成 She is a little, old lady.)
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2.2.2在两个修饰主语的短语之间加上逗号(句短可不加)：
1. While waiting for the bus on that cold rainy night, she started
2.At 10 o'clock the bus arrived.(不必写成 At 10 o'clock, the bus
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