On the basis of other researches,we have summarized the semantic features and relations of this prepositional structure in a sentence from three perspectives,that is,the three semantic relations of "在N的V下" with the main clause,the time relations of "在N的V下" with the main clause and the mutual semantic restrictions of them.

Based on the research work of the practitioners,this paper discusses the time relation in the management field,and standardizes the expression and their names.

By a thorough analysis of the eleven kinds of time relation structures and a comprehensive description of what are expressed in the English perfective, this article has drawn a conclusion: the English perfective indeed have the inherent semant.

Means to express time relationship in Russian simple sentences are flexible and varying,including structures with prepositions and structures without prepositions Moreover,prepositions play a vital part in such ex- pressions.

There is a time relationship between verb predicate and adverbial of time in any Russian simple sentence, which can be categorized into that of direct time and that of comparative time according to synchronization or unsynchronization of action and time.

In this article, weak synchronization is introduced as an efficient approach to specify temporal relationships among obj.

Temporal-Planning is the special schedule area in artificial intelligence accordingas restriction of Temporal-Relation.