—Sorry , I'm not good ___it .
A:at
B:in
C:to
- What present do you want to buy for your father?
- . They can keep his hands warm in winter.
A
B
C
D
X
分解反应
金属
纯净物
化合物
Y
化合反应
单质
混合物
I can't the ball. Where is it?
周长相等的图形,面积也一定相等。(判断对错)