He wished them "good morning" in an awkward hesitating undertone as if he were doubtful how his greetings would be received . 他尴尬地向他们问好，声音很低，又有些犹豫，好象担心他们会不睬他。
As soon as he finished, his supporters applauded vigorously, but most of the masses were taken aback and exchanged doubtful glances . 他的话完了，他的几个支持者拼命地鼓掌，而更多的人却噤若寒蝉，面面相觑。
It is doubtful that the diffusion or ideal mixing stage models can satisfactorily represent the behavior of gas in fluidized beds . 扩散模型或者理想混合级模型能否满意地表示气体在流化床中的性状是可以怀疑的。
The indian civilian, glancing at shelton in an affectionate and doubtful way, replied: "you haven't changed a bit, old chap. " 这位印度文官带着又真挚又怀疑的神情对谢尔顿瞅着答道：“你一丁点儿也没有变，老兄。“
For many minutes the struggle between the light bubble in which they floated, and the swift current, was severe and doubtful . 在此后好几分钟内，他们乘坐的这只轻如水泡的小船和奔腾的急流展开了一场胜负难决的激烈搏斗。
She could not understand why her mother should find such satisfaction in contemplating an enterprise of, to her, such doubtful profit . 她始终不明白，为什么她自己觉得是一件完全凭撞运气，好坏毫无把握的事儿，她母亲一提起来，却会那样高兴满意。
At that moment the doubtful attractiveness of romola's face was transfigured to the most loveable womanliness by mingled pity and affection . 这时候，罗摩拉的脸，她那令人捉摸不定的动人之处，转变成为怜悯和深情掺合而成的最最可爱的女性的温柔。
The ethics of his decision are doubtful 他的这一决定是否合乎道德规范值得怀疑。
It is doubtful that they will finish on time 他们是否将如期完成是值得怀疑的。
The ethics of his decision are doubtful 他的这一决定是否合乎道德规范值得怀疑
