Usages of rènzhēn
他 很 认真 地 学习， 下午 才 喝 茶。tā hěn rènzhēn de xuéxí, xiàwǔ cái hē chá.
He studies very seriously; he only drinks tea in the afternoon.
我们 应该 认真 学习。wǒmen yīnggāi rènzhēn xuéxí.
We should study seriously.
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