Usages of zài
她 现在 在 学习 呢。tā xiànzài zài xuéxí ne.
She is studying now.
他 在 做 这 个 吗？tā zài zuò zhè gè ma?
Is he doing this?
你 在 做 什么？nǐ zài zuò shénme?
What are you doing?
他 没 看见 我， 因为 他 一直 在 打 电话。tā méi kànjiàn wǒ, yīnwèi tā yìzhí zài dǎ diànhuà.
He didn't see me because he was on the phone the whole time.
我们 一直 在 学习， 下午 才 吃 午饭。wǒmen yìzhí zài xuéxí, xiàwǔ cái chī wǔfàn.
We were studying the whole time and only ate lunch in the afternoon.
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