Write summer in china in Chinese?

在中國的夏天 (Zài zhōng guó de xià tiān)

The summer in China

But if you mean: I spent my summer in China

在夏天的时候,我去了中國

(Zài xià tiān de shí hou, wǒ qùle zhōng guó)

During the summer, I went to China