The paper reports our study on the meaning knowledge and collocation knowledge ofsix high-frequency English verbs among Chinese students at three different languageproficiency levels. Based on the major findings, a model of bilingual mentalrepresentation is proposed, where the lexical links between an L2 word and itscorresponding LI words are differentiated, with the strongest one being the linkbetween the major sense of an L2 word and its L1 translation. The paper continueswith a description of the English vocabulary acquisition pattern among Chinesestudents. It is maintained that there are three stages in the acquisition-labeling,packaging and network building. During the process, Chinese mediation plays animportant role and facilitates initial vocabulary study However ,an in-depthactquisition is often hampered by the mediation.