下列行为符合男女同学正常交往原则的是[ ]
A.小颖怕别人说闲话,从不与男生交往
B.小雯与小强经常在班级探讨数学题
C.小明经常给女生起侮辱性绰号
D.小英和小刚常常单独在—起
答案:B
分别点燃下列物质后,在火焰上方罩上一个干燥的冷烧杯,烧杯内壁有水珠出现,然后迅速将该烧杯倒过来,向烧杯内注入少量澄清石灰水振荡,石灰水变浑浊。由此可推断该物质不可能是[ ]
A. 一氧化碳
B. 酒精
C. 甲烷
D. 石蜡
I wonder _______ on April 23, World Book Day.
Did you find some interesting books to read?[ ]
A. what did you do
B. what you did
C. what do you do
D. what you do