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a example 定 an example？
✗ 你會咁寫
Parents must be a example to their children.
✓ 應該係
Parents must be an example to their children.
「example」開頭係響音 (vowel sound)，所以要用「an」。
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點解你會咁寫
好多人背嘅版本係「a e i o u 前面用 an」，但真正嘅規則係睇個音。university 串法 u 開頭，讀出嚟係 /juː/，所以用 a；hour 串法 h 開頭，但 h 唔發音，所以用 an。讀一次出嚟就知。
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再睇多兩個例子
✗ It took a hour to finish.
✓ It took an hour to finish.
✗ He is studying in an university.
✓ He is studying in a university.
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