如图所示，P、Q叠放在一起，静止在水平面上，在下列的各对力中属于作用力和反作用力的是（ ）
A．P所受到的重力和Q对P的支持力
B．Q受到的重力和Q对P的支持力
C．P对Q的压力和地面对Q的支持力
D．Q对地面的压力和地面对Q的支持力
答案：D
作用力和反作用力是相互作用的两个物体间的作用力，P所受到的重力是地球给的，反作用力应该是物体吸引地球的力。所以A.B都不对；
P对Q的压力和Q对P的支持力互为作用力和反作用力，C错；
Q对地面的压力和地面对Q的支持力，是地面和Q之间的，所以D正确。
In the middle of the night, Peter's wife suddenly fell ill. She couldn't help crying, “Oh， my stomach! Get the 1 !” Peter, awaking from a deep sleep, thought his wife was only having a 2 dream. “Stop that noise,” he said to her. He turned over and tried to go to 3 again, but his wife still cried out, “Oh, help！help！ I'm sure I'm 4 .” Peter got out of bed and started 5 , but he could not find him any clothes. “Where is my shirt?” he asked. His wife was 6 ill to tell him, and she could only cry, “Oh, my 7 stomach!” As soon as he had put his clothes 8 , he said, “Now, my dear, are you quite 9 that you need the doctor? Surely you can wait 10 morning, can’t you?” “No, I can't. Go, go, go,” his wife shouted, “ 11 you will find me dead 12 the morning.” So Peter went out into the dark street. He had only gone a few meters 13 he heard his wife calling him again． “I’m 14 again now, and I shall not want the doctor.” she said softly. Hearing this, he started running as 15 as he could towards the doctor’s. When he arrived there, he knocked at the door loudly enough to wake 16 around. The doctor put his sleepy head out of the bedroom window and said, “Er? Who’s there?” “Oh, Doctor.” Peter called up to him, “I have very 17 news for you. My wife 18 ill with a terrible stomachache. I was on my way to bring you to her, but she called me back to say the trouble had suddenly 19 her. So you need not come. Go back to 20 now, and sleep well!”
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