Chinese Rocks

There is one character in these two sentences that has a different pronunciation, can you find it?

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這題你不是練好幾遍，笨得喔。

你不笨，是這題得練好幾遍喔

zhè tí nǐ bú shì liàn hăo jǐ biàn ？bèn de ō 。

nǐ bú bèn ，shì zhè tí děi  liàn hăo jǐ biàn 。

＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝

題tí ：a measure word for question

練liàn ：to practice

好hăo 幾jǐ ：several; many

遍biàn：.a word to express the number of times in doing 

something

笨bèn ：dull; foolish

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得de ：a particle used to link a verb or an adjective to a complement which describes the manner or degree

得děi：  have to; need; ought

＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝＝

Didn't you practice this many times? You are so stupid.

You are not stupid. It is because this has to be practiced many times.