如图所示的电路中,电源电压保持不变,闭合开关 S ,当滑动变阻器的滑片 P 向右移动时,电路中保持不变的是 ( )
A.用电器消耗的总功率
B.电压表 V 的示数与电流表 A 的示数的比值
C.电流表 A 的示数与电流表 A 1 的示数的差值
D.电压表 V 的示数与电流表 A 1 的示数的乘积
My brother has lost his watch. Now he is looking for_____.( )
A.oneB.thisC.thatD.it
Bill bought _____useful book._____book is very interesting.( )
A.a;TheB.a;AC.an; TheD.an; A
The game is too hard for me. I will certainly lose.
_______. You should never say no before you try.( )
A.Forget it!B.Come on!C.I'm sorry.D.Pardon me?
Tomorrow is Father's Day. What's your surprise for your father?
The first thing____ I will do is to make a card for him.( )
A.whoB.whereC.whoseD.that
I don't know during the summer vacation. Do you have any advice?
How about visiting Beijing International Horticultural Expo(北京国际园艺博览会)?( )
A.what should I doB.when should I go
C.what I should doD.when I should go