题干
The most important thing ____ when ____an emergency is to stay calm.
A：keep it in mind; deal with
B：keep in mind; dealing with
C：to keep it in mind; dealing with
D：to keep in mind; dealing with
答案(点此获取答案解析）
D
”是“方程
”表示焦点在y轴上的椭圆”的（ ）