珍珠的性状特征：（）
A.类球形、卵圆形
B.表面：具特有的彩色光泽
C.质地坚硬
D.断面：可见层纹
E.无臭，味淡
参考答案：A, B, C, D, E
Some of the exercises appear to be ________ ones that you have done, but after taking ________
second look, you will find that they are different. [ ]
A. 不填; the
B. the; the
C. the; a
D. the; 不填
用于显示部分查询结果的TOP短语，使用时需与之连用的短语是（ ）。
A． WHERE
B． FROM
C． GROUP BY
D． ORDER BY
