不对呀。(Búduìyā.)It is not right.

Explanation

“不对呀”这个短句一般用作插入语，位于句首。当事实与说话人所发现的不同或者是情况不正常时，常用这个短句来否定和质疑别人的话。说话时往往带有怀疑的语气。
“不对呀” is usually used as parenthesis at the beginning of a sentence. It is often used to deny or doubt someone else when the fact is not the same as the speaker’s. It contains doubtful tone.

Words:

补课bǔkè:make up lessons;
银行yínhánɡ:bank;
信用卡xìnyònɡ kǎ :credit card.

Sentences

1、甲：不对呀，刘老师没有说过晚上要补课呀！
Jiă: Búduìyā！Liú lăoshi méiyǒu shuōguò wănshang yào bǔkè ya!
A: It is not right. Teacher Liu did not say we would make up our lessons in the evening.

乙：哦，那可能是我记错了!
Yǐ: O ,nà kěnéng shì wǒ jìcuò le.
B: Oh, maybe I made a mistake.

2、甲：桌上放着银行催你信用卡还款的通知。
Jiă: Zhuōshang fàng zhe yínháng cuī nǐxìnyòngkǎ huán kuăn de tōngzhī.
A: The notice that the bank asks you to pay back your credit card is on the table.

乙：不对呀，我上个星期已经还了啊。
Yǐ: Búduìya，wǒ shàng gè xīngqī yǐjīng huán le ā .
B: It is not right. I paid it back last week.

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