Venomous snakes spit and hiss when they are cornered.

毒蛇在无法逃脱时会发出愤怒的呼呼咝咝的声音。

《牛津词典》

Probably back in some previous biology course you learned that snakes evolved from lizards, and that the first snakes weren't venomous and then along came more advanced snakes, the venomous snakes.

也许在以前的生物课上，你学过蛇是由蜥蜴进化而来的，而且最初的蛇是没有毒的，后来出现了更高级的蛇，也就是毒蛇。

youdao

Ok, venomous snakes are the ones that secrete poisonous substances or venom, like the snakes of the viper family or cobras.

毒蛇是一种分泌有毒物质或毒液的动物，像蝰蛇科的蛇或眼镜蛇。

youdao

As venomous snakes flee the flood, there could be a spike in snakebites.

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The 56km of rough, shark-infested waters and the venomous snakes for which the island is named usually put an end to any hope of escape.

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Of the 22 species of snakes within the Morganza Spillway, three -- the copperhead, cottonmouth and canebrake rattler -- are venomous.

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