Grammar Review: Sentence End “了”
I. “了” --- “up till now”
The particle “了” can also be used (1) at the end of a sentence (2) without time word. It tells in what stage an action is UP TILL NOW. It is very often used in a question.
你吃饭了吗？/ 你吃飯了嗎？Have you had your meal?
你看今天的新闻了吗？/ 你看今天的新聞了嗎？
Have you read / watched today's news?
II. Perfect Aspect Particle “了1” and the sentence end “了”
The combination of the two “了” tells how much (in quantity and in time) an action has been completed up till now.
我(昨天晚上)喝了三杯茶。 I had three cups of tea (last night).
我喝了三杯茶了。 I've been drinking tea up till now.
I've had three cups so far.
I may continue to drink more.
我学了两年汉语。 I studied Chinese for two years.
我學了兩年漢語。 (I may or may not study now.)
我学了两年汉语了。 I've been studying Chinese for two years.
我學了兩年漢語了。 (I may continue to study.)
III. Sentence end “了2” ------ change of state or situation
For any affirmative sentence (with action verbs or non-action verbs), adding “了” at the end will indicate a change of situation.
他不是我的朋友了。（他以前是我的朋友，现在不是了。）
我不去美国上大学了。（我本来打算去美国上大学。）
我不去美國上大學了。（我本來打算去美國上大學。）
不下雨了，我们回家吧！
不下雨了，我們回家吧！(The rain has just stopped, Let's go home. )
我以前每天看电视，现在忙了，没时间看了。
我以前每天看電視，現在忙了，沒時間看了。