高いんだ

It’s expensive.

→ 高い
phrase Uncommon #10,544
It’s expensive. Used to state or explain that the price or cost is high. The んだ adds an explanatory or emphatic tone.
JA: このアパート、家賃がめちゃ高いんだ。
EN: The rent for this apartment is really expensive.

冬のイチゴは高いんだ。

Strawberries are expensive in winter.

あの靴、高いんだからね。

Those shoes are expensive, you know.

このアパート、家賃がめちゃ高いんだ。

The rent for this apartment is insanely expensive.

牛肉はとても高いんだ。

Beef is really expensive.

なぜこの仕事は高いんだ?

Why does this job pay so well?

— ブレット・トレイン (2022)

家賃がすごく高いんだ。

The rent is really expensive.