了
le
(completed action marker)
(modal particle indicating change of state, situation now); (modal particle intensifying preceding clause)
了 — the completion and change-of-state marker
Originally a verb meaning 'to finish' or 'to complete,' 了 was extended to mark that an action is done or that a situation has newly changed. Its simple shape carries no visual clue to this grammar — the meaning comes entirely from how speakers borrowed it for function.
我吃了早饭，就去上班。
wǒ chī le zǎo fàn，jiù qù shàng bān。
After I ate breakfast, I went to work.
天气变冷了，你要多穿衣服。
tiān qì biàn lěng le，nǐ yào duō chuān yī fu。
The weather has turned cold, so you should wear more clothes.
Words with 了
说了算
shuō le suàn
to have the final say
一了百了
yī liǎo bǎi liǎo
(idiom) once the main problem is solved, all troubles are solved; death ends all one's troubles
罢了
bà le
a modal particle indicating (that's all, only, nothing much)
罢了
bà liǎo
a modal particle indicating (don't mind it, ok)
了然
liǎo rán
to understand clearly
不得了
bù dé liǎo
desperately serious
棒极了
bàng jí le
super
了不得
liǎo bu de
terrific
嘎了
gǎ le
(slang) (I'm, you're) toast; so screwed; it's game over (for sb); (sth) bit the dust
欧了
ōu le
(coll.) okay (loanword from "over")
临了
lín liǎo
at the last moment
这还了得
zhè hái liǎo dé
How dare you!