When his mother came in , he stopped .[ ]
A. cry
B. cried
C. to cry
D. crying
答案:D
写出下面每组数的最大公因数.
(1)3和7 9和16 11和20
(2)6和24 88和11 63和9
(3)12和l6 42和28 65和25.
请演示艾灸雀啄灸的操作。