32. —I must apologize for______ ahead of time.
—That’s all right.
A. letting you not know
B. not letting you know
C. letting you know not
D. letting not you know
答：B．动名词的否定式由not+动名词构成。
33. The missing boys were last seen ________ near the river.
A. playing B. to be playing
C. play D. to play
答：A．不定式做宾补表示该动作的全过程，而现在分词做宾补则表示该动作正在进行。此题通过last(最后那一刻)可判断A项。
34. The visiting minister expressed his satisfaction with the talks, __________ that he had enjoyed his stay here.
A. having added B. to add
C. adding D. added
答：C．分词做伴随状语。
35. The first textbooks _________ for teaching English as a foreign language came out in the 16th century.
A. having written B. to be written
C. being written D. written
答：D．C项强调正在进行的被动动作。B项强调将要进行的被动动作。
36. We agreed___________ here but so far she hasn’t turned up yet.
A. having met B. meeting
C. to meet D. to have met
答：C。agree to do...同意做……
37. The patient was warned ___________ oily food after the operation.
A. to eat not B. eating not
C. not to eat D. not eating
答：C。 warn sb. not to do / against doing 警告某人不要做某事
38. ___________ in thought, he almost ran into the car in front of him.
A. Losing B. Having lost
C. Lost D. To lose
答：C。be lost in thought 在沉思。 lost in thought=as he was lost in thought.