I. Choose the words whose underlined part is pronounced differently from that of the others in each group.
1. A. pain B. said C. afraid D. straight
2. A. ceiling B. neighbor C. vein D. freight
3. A. except B. there C. then D. hey
4. A. make B. playground C. station D. many
5. A. performed B. approached C. advertised D. murdered
6. A. illegal B. sign C. critic D. direct
7. A. terrified B. entertained C. produced D. engaged
8. A. cough B. laugh C. enough D. high
9. A. collect B. clean C. city D. cracker
10. A. buffalo B. unhappy C. pollution D. structure
11. A. collection B. comic C. concert D. volunteer
12. A. bread B. really C. head D. death
13. A. blood B. vocabulary C. doubtful D. boring
(in đậm đi, làm ko có in đậm là khó lắm)