治疗重症肌无力首选()。A．毒扁豆碱 B．毛果芸香碱 C．琥珀酰胆碱 D．新斯的明

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But  happy   Nobody   friends around

This morning a big rock was in the way. (86)_____knew where it was from. All the cars had to go(87) _____it. Ben saw the rock. He tried to move it. (88)_____it was so heavy. He called three of his (89)______to help. Little by little the rock was moved out of the street. They pushed it to a nearby park. Ben was (90)_____ to see people sit on the rock in the park.