One winter during college in New York, I took an 8 am history class to fulfill a requireme

One winter during college in New York, I took an 8 am history class to fulfill a requirement. It was 36 to get up for that class, but every morning I would 37 the cold winds and went to the lecture.
The professor for the class would step 38 into the room. He was terribly nervous about the class and always fixed his eyes on his book, never 39 us.
I felt that I needed to do something to 40 the boredom, so I tried to find something in his lecture to ask him, 41 me to pay attention rather than letting my eyes close. The first time 42 I raised my hand, he was surprised but was obviously 43 to have a question to answer. I continued to do this every day. The professor seemed to bee a bit more 44 and some other students even joined in. In fact, his answers were always 45. In this way, I learned quite a lot and realized the professor was indeed a/an 46 in his field.
On the last day of class we 47 our books and headed out. The professor stepped directly in front of me, with obvious 48, putting out his hand. He said, “49 you for making my class so interesting,” shaking my hand and smiling. I was so 50. To me, it had been a pleasant way to 51 the time in his lesson. I had no idea that my 52 had any effect on him or the others at all.
That 53 has stayed with me for 30 years. I don’t 54 the fact I learned in his class, but I’ll never forget the professor who taught me a lesson about the 55 of acts of kindness, indeed or not.
【小题1】A．impossibleB．roughC．naturalD．tough【小题2】A．slowB．braveC．lowerD．warm【小题3】A．shylyB．eagerlyC．proudlyD．hurriedly【小题4】A．looking down atB．looking up atC．looking up toD．looking down upon【小题5】A．ignoreB．delayC．stopD．understand【小题6】A．forcingB．allowingC．advisingD．persuading【小题7】A．whenB．in whichC．*D．that【小题8】A．impatientB．sorryC．shockedD．pleased【小题9】A．relaxedB．annoyedC．tiredD．determined【小题10】A．boringB．interestingC．puzzlingD．worrying【小题11】A．permanentB．temporaryC．expertD．fool【小题12】A．readB．copiedC．orderedD．gathered【小题13】A．pityB．effortC．humorD．guilt【小题14】A．ThankB．ForgiveC．BlameD．Praise【小题15】A．honestB．nervousC．surprisedD．disappointed【小题16】A．saveB．spendC．spareD．pass【小题17】A．storiesB．questionsC．appearanceD．care【小题18】A．momentB．opinionC．suggestionD．wish【小题19】A．likeB．knowC．recallD．believe【小题20】A．conceptB．rewardC．priceD．powerD