《大学英语》(上海复旦大学主编,文理科本科用教材)精读第一册第十单元第四行:...and how he was having trouble staying awake.(那时他要保持不睡觉很困难。);第二册第六单元十一行:...I’d have trouble getting back to sleep.(我就很难再重新入睡了。)及第三册第八单元十四行:They have trouble concentrating.(他们难以集中注意力。)这几句都是在trouble后省略了介词in,在英国英语中,特别是在口语中,介词in常在下列句型中被省略: “College English” (edited by Shanghai Fudan University, undergraduate textbooks for liberal arts and science) intensive reading the first line of the tenth unit of the first book: ...and how he was having trouble staying awake. (At that time, it was very difficult for him to stay awake. ); The second book of the sixth unit of the eleventh line: ... I’d have trouble getting back to sleep. (I will be difficult to re-sleep.) And the third volume of the eighth unit of the fourteenth line: They have trouble Concentrating. (They are difficult to concentrate.) These sentences are omitted after the introduction of the preposition in. In British English, especially in oral English, the preposition in is often omitted in the following sentence: