1. A conversational sentence translation apparatus comprising: input means through which a free conversational sentence in a first language is inputted in the apparatus; a semantic feature dictionary in which information on various semantic features is stored, said information on each semantic feature including a name of the semantic feature and at least one character string in the first language having the semantic feature, said character strings serving as elements of sentences in the first language; a bilingual database in which information on various conversational sentence examples is stored, said information on each conversational sentence example including a conversational sentence example in the first language, a translation in a second language of the conversational sentence example, and a string of semantic features contained in the conversational sentence example; an analyzer for, with reference to the semantic feature dictionary, extracting semantic features from the conversational sentence input through the input means; a semantic searcher for searching the bilingual database for the semantic features extracted by the analyzer to determine a degree of semantic coincidence between each conversational sentence example and the input conversational sentence and select a conversational sentence example having a highest degree of semantic coincidence; and display means for displaying the conversational sentence example selected by the semantic searcher and the translation thereof.