He unwarily treads upon a viper asleep just before his feet.

他不小心踩到正睡在他脚前蛇上。

Rattlesnakes belong to the viper family.

响尾蛇属于蛇科。

Any of several venomous snakes of the genus Cerastes, such as the horned viper, having hornlike projections over each eye.

冠雉属（形似火种树栖鸟，被用于比用）。