閉門造車

Simplified: 闭门造车

bìménzàochē ㄅㄧˋ ㄇㄣˊ ㄗㄠˋ ㄔㄜ

    • lit. to shut oneself away and build a cart (idiom)
    • fig. to work on a project in isolation, without caring for outside realities

Character by character

Sources