Mr. Jones is a renowned international authority on the problem of overpopulation in developing countries.
琼斯先生在发展中国家人口过剩问题方面是声誉卓著的国际权威。
The self-discipline required to drag myself out of bed eleven minutes earlier than usual was considerable.
这就要求我比平时早11分钟把自己从床上拽起来,这种自我约束是很艰苦的。