了(le) is one of the most frequently used function words in modern Chinese language, by itself, it has no concrete meaning, rather, it’s a ‘helper’ word used in many grammatical functions. Here are some important ways that 了 is used.

 

Completion of an Action

了 can be used after a verb to indicate the completion of an action

 

Because le is used most commonly for this purpose, elementary Chinese learners come to understand it simply as equivalent to English past tense. According to this understanding, verb +了 equals past tense, but that’s not accurate, because a verb’s completion can take place in the past, in the present, or in the future.

 

For example:

 

1. 去年夏天,他们有了一个孩子。
Last summer, they had a child. past

2. 现在,他们有了一个孩子。
Now, they have a child. present

3. 我们有了孩子以后,就没有这么多自由时间了。
After having a child, we won’t have as much spare time. future

Some Chinese learners assume that, since they just need put 了after the verb to render Chinese sentence in the past tense, then this rule must suit all Chinese verbs. Unfortunately, it’s not that simple; there are some rules, which must be observed:

 

1. Some verbs that describe a mental state or emotional feeling can not be followed by 了 to express past tense.

 

For example:

 

She felt very sad yesterday.

她昨天感觉了很难过。incorrect

她昨天感觉很难过。correct

 

Last year, she hoped to come back to Shanghai.

去年,他希望了回到上海。incorrect

去年,他希望回到上海。correct

 

Other verbs in this category: 想念 (miss),喜欢 (like),爱 (love),盼望 (look forward)

 

2. In a past tense sentence, if the object is an subordinate clause, the verb can not be followed by 了.

 

For example:

 

Many years ago, I realized that I loved Shanghai.

很多年前我就发现了我喜欢上海。incorrect

很多年前我就发现我喜欢上海。correct

 

Yesterday, I swore I would study Chinese very hard.

昨天,我发誓了我会努力学习汉语。incorrect

昨天,我发誓我会努力学汉语。 correct

 

3. In a dual-function constituent sentence, the first verb cannot be followed by 了.

 

For example:

 

He asked me to forgive him.

他请求了我原谅他。incorrect

他请求我原谅他。correct

 

Indication of a Change

了 can be used at the end, or in the pause position of a sentence to indicate a change, or that new information or a new situation has appeared - as the word ‘now’ is often used in English.

 

1. 他胖了。

He got fat.

This means he was not fat before.

 

2. 春天了,花都开了。

It is spring now, and the flowers are in bloom.

This means the flowers were not in bloom before.

 

3. 他是老师了。

He is a teacher now.

This means he was not teacher before.

 

4. 我儿子会唱歌了。

My son can sing now.

Thich means my son could not sing before.

 

Express Urging, Dissuasion, or Reminder

了 can be used at the end, or in the pause position of a sentence to express urging, dissuasion or reminder.

 

For example:

 

1. 走了!走了!已经八点了!(urging)

Go! Go! It’s already 8 o’clock!

 

2. 够了!不要再提这件事了! (dissuasion)

Enough! Don’t mention this ever again!

 

3. 下班了!我们回家吧。(reminder)

Work is finished! Let’s go home.

 

Fixed Phrases using 了

 

1. 太……了。Means ‘very’ or ‘very much’.

 

今天太热了。It is very hot today.

她太漂亮了。She is very beautiful.

我太喜欢上海了。I like Shanghai very much.

 

2. 该……了。Means: “It’s time to (action verb).”

 

该上班了。It’s time to go to work.

该睡觉了。It’s time to go to sleep.

该吃晚饭了。It’s time to have dinner.

 

3. 要……了 Means someone or something “is going to do (something).”

 

爸爸要去上班了。Dad is going to go to work.

天要下雨了。 It is going to rain.

 

4. 快(要)……了 Means something “will happen soon.”

 

我快30岁了。 I will soon be 30 years old.

圣诞节快来了。 Christmas is coming soon.

我快要冻死了。 I will soon freeze to death!