I. Choose the word whose underlined part is pronounced differently from that of the others.
1. A. humor B. hour C. highland D. hand
2. A. pesticide B. prevent C. reduce D. reuse
3. A. flow B. row C. know D. now
4. A. easy B. seat C. learn D. eat
5. A. phoned B. called C. cooked D. climbed
6. A. this B. thick C. math D. thin
7. A. proud B. about C. around D. would
8. A. health B. appear C. ready D. heavy
9. A. though B. throw C. through D. thought
10. A. nation B. vase C. nature D. grade
11. A. potatoes B. goes C. tomatoes D. diseases
12. A. choose B. child C. change D. chemistry