【正文】
eyed12. (should ) be 13. learned 14. had made 15. didn39。t see P5051. would buy → bought / shold buy / were to buy 2. smoke → shouldn39。t smoke / should not smoke 3. must → would / could / should → should have → had promoted → should be promoted 7. did39。t → hadn39。t left buy → could have bought → had taught → worked P5161. 我的想法是,在他們困難的時(shí)候要給他們以援助。 。 。 ,我們就可能成功了 P517 The United States is divided into telephone dialing areas. Each area has an area code. It is a threedigit number. You use this number to dial long distance calls. For example, you want to call 5552364 in South Carolina. But you live in Utah. You must dial 1 first and then the area code. It is 803. so you must dial 18035552364. When you do not know an area code, you can use the area code map in the telephone book. The map divides the United States into time zones. Notice that when it is 1:00 in California, it is 4:00 in Michigan.