This is the 7497th most frequent Japanese word.
入れよ
"入れよ" is a command meaning "put it in" or "insert it."
In this sentence, '入れよ' is used as a directive order, instructing someone to perform the action of putting something inside an object.
空瓶に水を入れよ。
Put water in the empty bottle.
Here, '入れよ' provides an imperative suggestion about arranging items appropriately, emphasizing care.
大切な物を忘れずにバッグに入れよ。
Don't forget to put important items in your bag.
In this case, '入れよ' serves as advice recommending an action for comfort or benefit.