● 按……计算→The farmers sell their apples by the pound.

● 就（气质，特征）而言→He is an artist by temperament（气质）.

用于被动语意，导出动作执行者：

The glass was broken by the boy.

by + 具体时间：

They usually have dinner by 8 o'clock.

by + 交通工具 (bus, train, plan...)：

He travelled to Paris by air/plane.

by the end of + 时间名词：到……末为止

By the end of last year, they had learnt 100 texts.

By the end of this term, they will have learnt 100 texts.

by then：到那时

He will graduate in 1999, by then he will leave Beijing.

by way of (= via)：经由，取道

They are going to the United States by way of Hong Kong.

by the way：顺便问

By the way, do you know where Mr. Li has gone?

by far：……得多（用于修饰比较级和最高级）

The book is by far the best on the subject.

by accident：不小心，与on purpose（故意地）语意相反

The wrong information was put into the computer by accident.