A:She's going to go swimming.
B:She's going to go hiking.
C:She's going to go shopping with her mother.
—Because she_________ a cold.
“他一生孤独,最大的精神支撑是内心崇高的社会理想,是一个状元告别仕途后仍念念不忘的兴国之梦。”这是对清末状元张謇的评价,他的“兴国之梦”是( )
方程x2+y2+4mx-2y+5m=0表示圆的充要条件是
下面哪项不属于生物防治的是( )