HSK 3
开心
kāixīn形
to feel happy; to rejoice; to have a great time; to make fun of sb
朋友来我家，我很开心。
Péng you lái wǒ jiā, wǒ hěn kāi xīn.
I am happy that my friend came to my home.
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New in the HSK 3.0 word list at level 3.