**Exercise 1: Choose the word whose underlined part is pronounced differently from the others.**

1. The answer is **D. allergy**. The "y" in "allergy" is pronounced as /i/, while the other options have the "y" pronounced as /ai/ or /i/.

2. The answer is **D. weak**. The "ea" in "weak" is pronounced as /i/, while the other options have "ea" pronounced as /ɛː/.

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**Exercise 2: Choose the correct answer**

3. The correct answer is **B. stay**. The complete sentence would be: "To stay healthy, you need between 1,600 and 2,500 calories."

4. The correct answer is **C. appointment**. The complete sentence would be: "Sorry! I’m busy tonight. I have an appointment with my doctor at 7 o’clock."