1. Trước hết bạn hãy đọc lướt qua tài liệu. Hãy xác định đâu là những đề mục chính, các phần, và cả những tài liệu liên quan? Mục đích của việc này là để nắm rõ những nội dung chính mà bạn cần quan tâm đồng thời bạn sẽ quyết định quá trình đọc sẽ đi theo hướng nào. | 64 FLUENT ENGLISH If you are very close to sure about something use couldn t verb or can t verb. Sam couldn t be old enough to drive yet. He seems too young. The grass can t be dry. It just rained last night. If you area little less certain then use must not verb. Troy must not be at work today. He was out sick yesterday and his office is empty. When you are less than 50 percent sure of something use may not verb or might not verb. Frederic may not be available on Tuesday afternoons. I don t know his schedule. Jessica might not be a member of my gym. I haven t seen her there. PRACTICE EXERCISE 1 Fill in each blank with the verb form that expresses the appropriate amount of certainty. First use the positive form. In some cases there may be more than one correct answer. 1. George like coffee because he always has a cup in his hand. 2 Billy be asleep because it s after midnight and he went to bed three hours ago. 3. Anne be outside working in the garden but I m really not sure. 4. If you feel awful but don t have a cold you have allergies. 5. That animal looks like a dog but it s not it be a coyote. Now use the negative form. 6. Danny be hungry asked him to eat with us if he wanted to. 7. The museum be closed. It closes at 5 00 and it s only 4 30. 8. He only moved here a week ago so he know anyone yet. 9. Bob gets off work at 5 00 so 6 00 be too early for dinner. 10. Thirty minutes be enough time to get there it takes at least 40 minutes. TOPIC 2 Degrees of Certainty in the Past Tense Use the simple past-tense form when you are 100 percent certain. Terrence was home last night. I called him and talked to him. Dennis ate a big salad for lunch. I saw him eat it. Use must have participle when you are almost certain. Karen must have been hungry. She ate three eggs for breakfast. You must have had a good time. You look happy. When you are less than 50 percent certain use may have participle might have participle or could have participle. Ken may have been at work .
