有“非洲屋脊”之称的是（    ）

下列哪一项不属于细胞膜的功能(     )

    Everybody has his own hero in mind and is always trying to copy his behaviors in life. As for1, my grandfather is just that man. My grandfather had a small farm. He also worked in a 2.

    One autumn, most of the farmers in the village were all3, so he promised to help his neighbor harvest the corn as he often did.4, after harvesting his own corn, Grandpa's little corn machine broke.What was5, the factory where Grandpa worked made the workers have extra work. He had to leave the farm6and didn't get back until very late. It now seemed7to help out his neighbor because he really had no free time.

    One night, Grandpa 8that he wouldn't let his neighbor's harvest rot in the field.9a machine, he'd harvest it by hand.

    "I don't think you'd have time to do it," said my grandma."Besides,it would be too dark to do10at night." 

    "I know of one night that I could do it!" he11."There's still one more full moon in October.12the weather is clear, I think I can do it."

    A few days later, after a long shift  at the factory, my grandpa went to the 13.The weather was cold but clear. He cut all the corn through the night to keep his word.

    Sometimes, when I want to14responsibilities, I'd see my grandfather15corn in the light of the harvest moon. Behind him, row after row of corn stocks stand at attention in respect for a man who keeps his word.