Some cats like to catch small birds, like canaries. If someone looks very proud or satisfied with himself, we say he " looks like the cat that ate the canary."

有的猫喜欢抓小鸟，比如金丝雀。如果有人看起来很骄傲，或对自己很满意，我们就可以说他looks like the cat that ate the canary(感觉自我良好)。