如图所示，一儿童玩具静止在水平地面上，一个幼儿沿与水平面成53°角的恒力拉着它沿水平面运动，已知拉力F=4.0N，玩具的质量m=0.5kg，经过时间t=2.0s，玩具移动了距离x=4.8m，这时幼儿松开手，玩具又滑行了一段距离后停下．
I've asked him __________ us for dinner, but he said he was quite busy.
如图表示甲状腺活动调节的示意图。下列对这一调节的叙述不正确的是
以36km/h的速度沿平直公路行驶的汽车，刹车后获得大小为a=4m/s2的加速度，刹车后的第3s内，汽车走过的路程为（ ）
从方框中选择最佳选项完成对话, 有两项多余。
A. Are you having a party?
B. What is the weather like?
C. Where are you?
D. What do you do?
E. I'm calling to say happy birthday.
F. What are you doing?
G. How about you?
A: Hello, Sam?
B: Maria?Hi! ____
A: I'm in Australia! ____
B: Oh, thanks.
A: So how is it going there?
B: Great! ____
A: Pretty good. ____
B: I'm having a party. My whole family is here.
A: That sounds like fun. ____
B: Terrible. It's cold and raining.
