硬い

彼（かれ）は頭（あたま）が固（かた）い。

He is thick-headed.

彼（かれ）は自分（じぶん）の神（かみ）を堅（かた）く信（しん）じていた。

He had a firm belief in his God.

彼（かれ）は考（かんが）えがかたい。

He is rigid in his views.

彼（かれ）は義務（ぎむ）を固（かた）く守（まも）る。

He is very observant of his duties.

肉（にく）が硬（かた）くて切（き）れない。

The meat cuts tough.

頭の固（あたまのかた）いやつだな。

You've got a one-track mind.

固（かた）いものは食（た）べないでください。

Don't eat hard foods.

固（かた）いこと言（い）うなよ。

You don't have to be so formal.