This paper compares, using our Japanese data, word repetitions with error repairs in terms of their temporal structures in order to examine whether or not the prolongation of first tokens in word repetitions, observed by Den and Clark (2000), is really an effect of the speaker’s strategy. Analyses of 10 task-oriented Japanese dialogues reveal a difference between word repetitions and error repairs for the data involving cut-off in first tokens; in both types of disfluencies, the final phoneme of the first token is considerably prolonged, but the degree of the prolongation is much greater in word repetitions than in error repairs. These results support our view that prolonged first tokens in word repetitions are a product of a process under the speaker’s control or intention.