To mind or care about something; to be concerned (often seen in negative forms like '構わない' meaning 'it doesn't matter').
遅れても構いませんよ。ゆっくり来てください。
It's okay if you're late. Please come slowly (take your time).
そんな小さなことに構う必要はない。
You don't need to worry about such a small thing.
どう思われるか構わないから、自分のやりたいことをやる。
I don't care what people think; I'll do what I want.
彼は見た目にあまり構わない性格だ。
He doesn't care much about his appearance.
To be an issue or to matter; to create inconvenience or have significance.
時間の差は構いませんが、締め切りは守ってください。
Small differences in time don't matter, but please meet the deadline.
値段が少し高くても構わないと言った。
He said he didn't mind if the price was a bit higher.
その程度の汚れなら構わないと思う。
I don't think that level of dirt is a problem.
To keep company with, to look after, to attend to someone; to give attention or play with someone/something (often written in kana).
休みの日は子どもを一日中構って遊んだ。
On my day off I spent the whole day playing with my children.
猫が構ってほしそうにソファの上で鳴いている。
The cat is meowing on the sofa as if it wants attention.
祖父の病院にはよく行って、話し相手として構っている。
I often visit my grandfather in the hospital and keep him company.
To interfere with or meddle in someone else's affairs; often used negatively to tell someone not to get involved.
余計なことに構うな。自分の仕事に専念しなさい。
Don't meddle in unnecessary things. Focus on your own work.
隣人の家庭のことに構いすぎるのはよくない。
It's not good to interfere too much in your neighbor's family affairs.
他人の過去に構いすぎると人間関係が壊れることがある。
If you pry too much into someone's past, relationships can break down.
To tease or make fun of someone (transitive), often playfully or to get a reaction.
子どもたちが新しい友達をからかって構っていた。
The children were teasing the new friend to get attention.
彼は妹をからかって構うのが好きだが、時々やりすぎる。
He likes teasing his younger sister, but sometimes goes too far.
Archaic meaning: to banish or prohibit. Rarely used in modern Japanese, found in classical texts.
古文献の一節で、『構ふ』が追放の意味で用いられているのを見た。
I saw a passage in an old text where '構ふ' was used to mean 'banish'.