问题
单项选择题 A1型题
再生障碍性贫血引起贫血的最主要原因是（）
A.造血原料缺乏
B.无效性红细胞生成
C.红细胞破坏过多
D.骨髓造血功能低下
E.失血
答案
参考答案：D
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再生障碍性贫血引起贫血的最主要原因是（）
A.造血原料缺乏
B.无效性红细胞生成
C.红细胞破坏过多
D.骨髓造血功能低下
E.失血
参考答案：D
| 完形填空。 American people like to 1 "Thank you" when others help them or say 2 to them. Many Chinese people do so, 3 . It is a very 4 . You must say "Thank you" when someone passes you something on the table, when someone 5 the door open for you, when someone says you do your work 6 , or you buy a nice thing or your city is 7 . "Excuse me" is another sentence (句子) they often say. When you hear someone say "Excuse me" 8 you, you know he wants to pass you without touching (接触) you. If you want 9 others, say "Excuse me" first, and then begin talking. Let's 10 "Thank you: and "Excuse me" from now. | ||||
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