Write the correct form of the given word. 18. Using computers has a effect on children's learning. (BENEFIT) 19. People should be encouraged to buy smaller, more cars with fewer toxic emissions. (ECO...

18. Using computers has a beneficial effect on children's learning. 19. People should be encouraged to buy smaller, more economical cars with fewer toxic emissions. 20. His inability to speak English puts him at a disadvantage when he attends international conferences. 21. The underlined part that needs correction is "the" should be replaced with "a". So the correct answer is B. 22. I am not working tomorrow, so I don't have to get up early. 23. You should bring an umbrella with you. 24. We have to make every effort to recruit a sufficient number of specialists. 25. You mustn't talk during the exams. 26. You mustn't stay up late. Unit 9.3 1. A. both (the "th" sound in "both" is different from the other words) 2. C. birthday (the stress is on the first syllable, while in the other words it's on the second syllable) 3. C. hybrid 4. B. charge 5. A log in