My cousin is in middle school

表兄───older male cousin;中学───middle school

My older male cousin was very happy and undertake to have a trip with me!───我的表兄非常开心，他承诺带着我一同去旅行。

My older male cousin is 3 years older then me, but I am taller.───我比表哥小三岁，但是我比他高。