We developed a prototype system to support telecommunication by using keywords selected by the speaker in a videoconference. In the traditional presentation style, a speaker talks and uses audiovisual materials, and the audience at remote sites looks at these materials. Unfortunately, the audience often loses concentration and attention during the talk. To overcome this problem, we investigate a keyword presentation style, in which the speaker holds keyword cards that enable the audience to see additional information. Although keyword captions were originally intended for use in video materials for learning foreign languages, they can also be used to improve the quality of distance lectures in videoconferences. Our prototype system recognizes printed keywords in a video image at a server, and transfers the data to clients as multimedia functions such as language translation, three-dimensional (3D) model visualization, and audio reproduction. The additional information is collocated to the keyword cards in the display window, thus forming a spatial relationship between them. We conducted an experiment to investigate the properties of the keyword presentation style for an audience. The results suggest the potential of the keyword presentation style for improving the audience's concentration and attention in distance lectures by providing an environment that facilitates eye contact during videoconferencing.