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。
At that time, however, she was not only the largest ship that had ever been built, but was regarded as unsinkable,
当时,这艘轮船不仅是造船史上建造的最大的一艘船,而且也被认为是不会沉没的。