尽管吸烟能导致肺癌这个令人挠头的难题也是经历了数十年的探索才最终得出了结论。
Even the smoking-lung cancer connection took decades of epidemiological head-scratching to figure out.
对于五角大楼、情报机构、美国国家航天和宇宙航行局所有的努力来说，预测本钱和判断全寿命费用是一项令人挠头的工作。
For all the effort the Pentagon, the intelligence agencies and NASA put into it, cost estimating and judging life cycle costs is daunting work.
她精于分析，令人惊讶，能够解决让警方挠头的各种奇案。
She uses her surprising analytical acumen to solve mysteries that have stumped the police.
她精于分析，令人惊讶，能够解决让警方挠头的各种奇案。
She uses her surprising analytical acumen to solve mysteries that have stumped the police.
应用推荐