Stephenson shows the strain of working with daniel on toilet training .
斯蒂芬森在训练丹尼尔上厕所的工作中感到的压力。
And professor stephenson said second-hand smoke had been linked to chest infections , asthma and ear problems in children .
stephenson教授说,二手烟已经被发现与儿童患胸部感染、哮喘以及耳部疾病有关。
Boeing has conducted extensive research and development on additive manufacturing methods since 1997 according to daryl stephenson a company spokesman .
据波音新闻发言人darylstephenson介绍,公司从1997年就对再加工方法进行深入的研发。
At one end of a cavernous hall sits the first practical steam locomotive , designed in 1829 by george stephenson , an english engineer .
Metropolitan police commissioner sir paul stephenson resigned on sunday and assistant commissioner john yates quit on monday over the hiring of former now executive editor neil wallis .