题目

完形填空 A high school history teacher once told us. “If you make one close friend in school, you will be most fortunate. A true friend is someone who stays with you for life.”1teaches that he was right. Good friendship is just not easily2. It is possible that we simply do not stay in one place long enough for3friendship to4. However, there can be5disagreement on the need for each of us to think carefully about the kind of friendship we want. To most of us, friendships are considered very important, but we need to have it clear in our6what kinds of friendship we want. Are they to be cl下列关于免疫对人体的主要作用的叙述不正确的是(??? )A. 免疫总是对人体有益的B. 器官移植能否成功与免疫反应有关C. 抗体是一种蛋白质D. 过敏反应是免疫功能失调引起的