問題補充：
單選題
Forty-five students _________ a class is the proper number according to a study in the U．S．, published in a magazine last month．A.makes up ofB.making up ofC.made ofD.making up
網(wǎng)友答案：
熱心網(wǎng)友 1樓
B解析making up of“組成”，現(xiàn)在分詞作定語，相當(dāng)于定語從句who make up of a class。
