Usages of sānshí
这 次 考试 至少 要 写 三十 个 句子， 很多 人 最后 写 了 超过 四十 个 句子。zhè cì kǎoshì zhìshǎo yào xiě sānshí gè jùzi, hěnduō rén zuìhòu xiě le chāoguò sìshí gè jùzi.
For this exam you have to write at least thirty sentences; many people ended up writing more than forty.
我 在 这 个 城市 住 了 三十 天 了。wǒ zài zhè gè chéngshì zhù le sānshí tiān le.
I have lived in this city for thirty days.
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