题目

 It is said that Nigeria is _______ Great Britain. A. three times the size than B. the size three times of C. three times as the size of D. three times the size of 答案：解析：选D。考查倍数的表示方法。①倍数+比较级+than结构；②倍数+as +原级+as；③倍数+the length/size. . . of。只有D项符合。如右图，以等边△OAB的高OC为边向逆时针方向作等边△OCD，CD交OB于点E，再以OE为边向逆时针方向作等边△OEF，EF交OD于点G，再以OG为边向逆时针方向作等边△OGH，…，按此方法操作，最终得到△OMN，此时ON在OA上．若AB=1，则ON= ．