snake
The French word for 'snake' is 'serpent'. It is used exactly like 'snake' in English and can refer to any elongated, legless, carnivorous reptile of the suborder Serpentes. Just like in English, this word can be used figuratively in French to refer to someone who is treacherous or sly.
I am afraid of snakes.
This sentence indicates that the speaker has a fear of snakes. 'j'ai peur des' is a common phrase used to express fear of something in French.
The snake is in the cage.
This sentence is used to denote the location of a snake. 'est dans' is used to say 'is in' with the preposition 'dans' denoting the location.
The child is watching the snake at the zoo.
This sentence implies an ongoing action by the child. The 'au' in 'au zoo' is a contraction of 'à le' which is used before masculine nouns.