Usages of xiānsheng
先生 想 办理 挂失。xiānsheng xiǎng bànlǐ guàshī.
The gentleman wants to process a loss report.
先生， 请 带 有效证件。xiānsheng, qǐng dài yǒuxiàozhèngjiàn.
Sir, please bring valid identification.
那 位 老 先生 在 浇水。nà wèi lǎo xiānsheng zài jiāoshuǐ.
That elderly gentleman is watering the plant.
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