He has come to be recognized as an expert in the problem of overpopulation and food supply.
由于他的经验促使他终于成为了公认的人口过剩和食物供应问题的专家。
Her shopping had tired her and her basket ad grown heavier with every step of the way home.
去商店买东西把她搞得筋疲力尽;在回家的路上,她每走一步,就感到手里的篮子又重了一点。