Usages of kāi
我 先 开 灯， 再 看 书。wǒ xiān kāi dēng, zài kàn shū.
I will turn on the light first, then read.
她 把 灯 开 了， 我 就 看 书。tā bǎ dēng kāi le, wǒ jiù kàn shū.
She turned on the light, and then I read.
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