延長的英文：
to extend; to prolong; to lengthen

extend是什么意思：
v. 延长；延伸；扩大；延续；伸，伸出

This will extend the life of the drive.
这样会延长驱动装置的寿命。

Extended consciousness was his line.
延展清醒意识是他的本行。

They extended their citizenship cautiously but steadily.
他们慎重而稳步地扩大授与公民权的范围。

prolong是什么意思：
v. 延长，拖延，延期

Hospitalization may be prolonged.
住院期可能延长。

addition or extension that prolongs sth
增加或延长的部分.

Prolonged negotiation was not desirable.
拖长了的谈判并不是大家所想要的。

lengthen是什么意思：
v. （使）延长

To save time is to lengthen life
节约时间就是延长生命

As winter gave way to spring the days began to lengthen.
冬去春来时，白天开始长了起来。

As winter gave way to spring the days began to lengthen
冬去春来时，白天开始长了起来。