不以为然

bù yǐ wéi rán

to disagree; not to think it right

Character by character

不bù
not

以yǐ
take

为wéi
as

然rán
right

我劝他别去，他却不以为然。

I told him not to go, but he didn't agree.

Tone: neutral.

Means 'disagree', not 'think nothing of it' (that is 不以为意), a classic mix-up.

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