在家 (zài jiā) means “to be at home; (at a workplace) to be in (as opposed to being away on official business 差); (Buddhism etc) to remain a layman (as opposed to becoming a monk or a nun 家)”. It is an HSK 1 Chinese word in the HSK 3.0 vocabulary.
周末我在家。
Zhōumò wǒ zàijiā.
I'm at home on weekends.
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