完形填空。从A、B、C、D四个选项中选出最佳答案。

    Mr. Smith lived in a village（村庄）. He had a few farms（农场） and about twenty people working for him. He often told them 1hard and be honest(诚实的).

    One day he went to a farm and worked with the workers there. Soon it was time 2 lunch. He put 3 nice bread on the table and went out. A few minutes later, he came back again but he couldn't find the bread. "Who ate 4 on the table?" he shouted.

    Some of the workers answered, "We didn't."  The others said, "We saw nothing."

    "Well," said Mr. Smith, "5 are a lot of mice(老鼠) in the rooms, you know. So I put some poison（毒药） in the bread. 6 they eat, they must die. Then I can kill them."

    As soon as he finished, four workers began to cry. "Oh, dear!"

    "7?" asked Mr. Smith.  "We ate the bread when you were out. We are going to die." One of them cried.  "8," Mr. Smith said 9 a smile, "I only 10 you. Use your head."

小强为“探究滑动摩擦力大小（f）与哪些因素有关”，将家里的可调速跑步机传送带调成水平，找来两个相同的长方体木块（每个重G，上表面ABCD面积为2S₀，较光滑；下表面A′B′C′D′较粗糙；侧面CDD′C′面积为S₀，和“下表面”一样粗糙）．用测力计拉着一个木块（其上可加放木块），维持木块在传送带上对地静止并读出拉力T。为确定f与压力F、接触面粗糙程度、相对运动速度、接触面积大小的关系，小强所做实验记录如下：

— You're big.

—No, I am ____.

Only when we realize how serious the environment is damaged, _______ is usually ignored, ______ try our best to fight against it.

侦察兵为及早发现敌军骑兵的活动，常把耳朵帖在地面上听，就能判断附近是否有敌人的骑兵，下列解释错误的是（  ）