is good at的同义句是do well in.is good at意思是擅长。The boy is good at playing chess.这个男孩擅长下棋。这句话也可以说the boy does well in playing chess。
The little girl is good at singing and dancing.这个小女孩擅长唱歌跳舞。或者是the little girl does well in singing and dancing.
