A:省力和改变力的方向
B:省力和省功
C:省力和省距离
D:上述说法都正确
大规模开发和利用太阳能时,下列困难中,目前人们所关注解决的重点是( )
A. You're welcome.
B. What shape would you like?
C. I'd like some cherries, too.
D. What kind of pudding would you like?
E. Yes. I want to buy a pudding.
A: Can I help you?
B:____
A:____
B: I'd like a chocolate pudding.
B: I'd like a heart-shaped pudding.
A: Anything else?
B:____How much are they?
A: 70 yuan.
B: Here is the money.
A: Thank you.