社会保险经办机构和地方税务机关可以从基本养老保险基金中提取一定比例的费用，以弥补其开展业务所需经费的不足。
参考答案：错
Mr. Wang and his students _____ a lesson now. [ ]
A. are having
B. had
C. have
在SQL语言的SELECT语句中，用于实现选择运算的子句是______
A．FOR B．IF C．WHILE D．WHERE
