9. The apparatus according to claim 1 , further comprising a delay unit that computes a first difference by subtracting a second time point at which the source speech is received from a first time point at which the translated speech is determined to have been generated in all of the target languages, and delays output of the translated speech and the source speech until the first threshold time has passed since the second time point, when the computed first difference is less than a first threshold time determined in advance, wherein the output unit outputs the translated speech and the source speech after the delay unit delays the reproduction.
9. The apparatus according to claim 1 , further comprising a delay unit that computes a first difference by subtracting a second time point at which the source speech is received from a first time point at which the translated speech is determined to have been generated in all of the target languages, and delays output of the translated speech and the source speech until the first threshold time has passed since the second time point, when the computed first difference is less than a first threshold time determined in advance, wherein the output unit outputs the translated speech and the source speech after the delay unit delays the reproduction. 10. The apparatus according to claim 9 , further comprising a shortening unit that shortens a reproduction time of the translated speech and the source speech by a length of a second difference computed by subtracting the first threshold time from the first difference, when the first difference is more than the first threshold time.