Why does 電池 take the を particle


The sentence

咲は電池{でんち}を時計｛とけい｝に入｛はい｝れました。

Translates as "Saki put the batteries in the watch" but would would 電池 take を
in this case?




> 咲【さき】は電池{でんち}を時計｛とけい｝に入｛い｝れました。

As noted in the comments, the verb in your sample sentence is 入【い】れます・入【い】れる,
not 入【はい】ります・入【はい】る. The former with れ is the transitive form meaning _"to put
something into something else"_ , whereas the latter with り or る is the
intransitive form meaning _"to enter into something"_. Since the verb in your
sample sentence is transitive, it takes an object, and Japanese grammar
requires that the object is marked with the を particle.

