I. Choose the word whose underlined part is pronounced differently from the others.
1. a. laugh b. cough c. bought d. tough
2. a. game b. gym c. girl d. bag
3. a. calorie b. labour c. community d. volunteer
4. a. environmental b. benefit c. service d. sick
5. a. danc
ed b. help
ed c. watch
ed d. enjoy
ed