Usages of tiān
姐姐 毕业 那 天， 父母 既 高兴 又 有点儿 难过。jiějie bìyè nà tiān, fùmǔ jì gāoxìng yòu yǒudiǎnr nánguò.
On the day my sister graduated, our parents were both happy and a bit sad.
这 几 天 我 很 忙。zhè jǐ tiān wǒ hěn máng.
These past few days I have been very busy.
这 几 天 作业 太 多， 开心 的 心情 都 变成 了 受不了 的 压力。Zhè jǐ tiān zuòyè tài duō, kāixīn de xīnqíng dōu biànchéng le shòubuliǎo de yālì.
These days there’s too much homework; my happy mood has all turned into unbearable pressure.
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