必须 vs 必需

Same bìxū: 必须 is the adverb "must" before a verb (必须去医院); 必需 is "essential" and sticks to nouns (必需品).

必须必須

bìxū ㄅㄧˋ ㄒㄩ

to have to; must; compulsory

明天我必须去医院。

I have to go to the hospital tomorrow.

必需

bìxū ㄅㄧˋ ㄒㄩ

to need; to require; essential

摄像机对我而言是必需品。

The camera was essential for me.

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