One of the controversial issues regarding the locative inversion construction (LIC) in the English language relates to the constraints on verb types . There are three influential hypotheses in this area,known as Hoekstra and Mulder's analysis,Culicover and Levine's analysis and Birner's analysis respectively . The early understanding assumed that it was the unaccusative verbs,which were permitted in LIC,whereas,in the most cases,the unergative verbs were not permitted,except for the subtype of motion,such as walk,enter,when they were used together with a directional PP . Hoekstra and Mulder (1990) propose that LIC embeds a small clause,which licenses the so-called process of unaccusativization—the shift of unergative-type to unaccusative-type,when an unergative verb of motion occurs in a directional construction .However,Culicover and Levine (2001) argue that it is the distinction between light inversion and heavy inversion,rather than the distinction between unaccusative verbs and unergative verbs,that predicts the acceptability of LIC,due to the fact,noticed by Levin and Hovav (1995),that many other unergative types may occur in LIC,including swim-type,glitter-type,f lutter-type,and even work-type,along with the unergative verbs of motion .Culicover and Levine's analysis suggests that the acceptability of a unergative verb should be highly associated with the co-occurrence of a heavy subject in the same sentence .But the further data research,conducted by Birner (1994 ;1995),Birner and Ward (1998) and Hovav (1995),support the evidence that subjects in the majority of LIC are heavy,since they have to carry complex new information .Instead of the syntactic-semantic approach,Birner's analysis adopts the pragmatic approach and explores the pragmatic constraints of informationally-light verbs . The above three analyses shed light on the conclusion that it is the integration of syntactic,semantic and pragmatic factors that contributes to the constraints on verbs in LIC .Why is the sentence″Into/Out of the room walked John″more acceptable,while″* To the room walked John″ is less acceptable ?It is the syntactic-semantic explanation which permits the unergative verb walk to occur in LIC through the process of unaccusativization .The difference between the″into/out of the room″and″to the room″is that,the former emphasizes the bipolarity of motion,while the latter the process of motion .The pragmatic explanation makes it clear that the initial position in a sentence must provide the topicalized information,which can be offered by the bipolarity of motion,but not by the process of motion .