To express that something happened later than expected, you can use 才 (cái). In English, this might be expressed with "as late as" or "not until." This form is often used with a time of some sort, like a specific time of day, age, etc. This pattern is essentially the opposite of using 就 (jiù) to express earliness.
Subj. + Time + 才 + Verb
Wǒ zuótiān wǎnshang shíyī diǎn cái dào jiā.
I didn't arrive at home until eleven o'clock last night.
Tā èrshí-wǔ suì cái shàng dàxué.
He didn't go to college until he was 25.
Tā sìshí suì cái jiéhūn.
She didn't get married until she was forty.
Wǒ nǚ'ér zuótiān shí'èr diǎn cái shuìjiào, zuòyè tài duō le.
My daughter didn't go to bed until 12 o'clock yesterday. Too much homework.
Nǐ jiǔ diǎn shàngbān, bā diǎn bàn cái qǐchuáng?
You start work at nine o'clock, but don't get up until 8:30?
Fēijī gānggāng cái qǐfēi, wǎndiǎn le liǎng gè xiǎoshí.
The airplane just took off. It was delayed for two hours.
Diànyǐng qī diǎn bàn kāishǐ, kěshì yīnwèi dǔchē, wǒmen bā diǎn cái dào.
The movie began at 7:30, but we didn't arrive until eight because of traffic.
You can use 才 alone with the verb to indicate the lateness when the context is clear:
Nǐ zěnme cái chī wǎnfàn? Yǐjīng shí diǎn le.
How come you are eating dinner now? It's 10 pm.
Nǐ zěnme cái lái? Wǒmen děng le bàn gè duō xiǎoshí.
How come you came here so late? We've waited for more than half an hour.
Note that verbs following 才 should not take 了.
- 我昨天晚上十一点才到家了。 <<< BAD EXAMPLE, never say it this way!
Wǒ zuótiān wǎnshang shíyī diǎn cái dào jiā le.
- 她四十岁才结婚了。 <<< BAD EXAMPLE, never say it this way!
Tā sìshí suì cái jiéhūn le.
[adapted from AllSet Learning Chinese Grammar Wiki, Creative Commons License BY-NC-SA 3.0]
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