Where possible, reduce the use of "which," "who" "that" "whom" "whether... or not" etc.

Example:
Unnecessary: It is a truth that is universally acknowledged that a single man in possession of a good fortune must be in want of a wife. (用两个 that’s，读起来很别扭)
Better: It is a truth universally acknowledged that a single man in possession of a good fortune must be in want of a wife. -- Jane Austin
注：被动语态修饰的名词通常不须用关系代词。

Unnecessary: In 1970 India dedicated a nuclear power plant near Bombay, which was built with American assistance.
Improved: In 1970 India dedicated a nuclear power plant near Bombay, built with American assistance.

Unnecessary: During this period, Churchill spoke for a nation which was undivided and curiously happy, as it has never been in my lifetime, before or since.

Improved: During this period, Churchill spoke for a nation undivided and curiously happy, as it has never been in my lifetime, before or since.

Unnecessary: Justice theories have a long tradition, which goes back to Plato and Aristotle in the 5th century B.C.

Improved: Justice theories have a long tradition, going back to Plato and Aristotle in the 5th century B.C.

Unnecessary: Shirley Temple’s father blew nearly the entire $3 million that she made by tap dancing which made her famous in the movies.
Improved: Shirley Temple’s father blew nearly the entire $3 million she made tap dancing her way to fame in the movies.

Unnecessary: We told them they were the victims who deserved sympathy the most.
Improved: We told them they were the victims, most deserving of sympathy.

Unnecessary: Only a person who is oblivious* to the facts of modern life would doubt the need of vocational education today.
Better: Only a person oblivious to the facts of modern life would doubt the need of vocational education today.

Unnecessary: Not everyone in North America likes the taste of green tea, whether it contains caffeine or not.
Better: With or without caffeine, not everyone in North America likes the taste of green tea.

Unnecessary: Usually the Washington family married people who were socially better off than themselves, but the second marriage of George’s father was an exception.
Better: Usually the Washingtons married their social betters, but the second marriage of George’s father was an exception.

Unnecessary: In some instances, a letter can take ten days by air and six to eight weeks by ship to reach the person to whom the letter is addressed.
Better: In some instances, a letter can take ten days by air and six to eight weeks by ship to reach its intended receiver.