(届辽宁省大连市第三中学高三上学期期末考试英语试卷)The topic, _______ we devoted a heated discussion last night, is a hot issue at present.
22. He demanded that such things_____ from happening again.
21._____by a desire to learn, he was not interested in children’s play and adventure when he was young.
20. The flu is believed________by viruses.
19. They________a lot of suggestions for improving the workers’ living conditions.
18. After having gone____-far, I didn’t want to turn back.