One of the most identifying features of speech translation is the fact that it must be performed in real time while the speaker is speaking, and thus it is necessary to split a constant stream of words into translatable segments before starting the translation process.
this trend is not entirely unexpected because it is not possible to completely accurately guess syntactic constituents from every substring w. For example, parts of the sentence "in the next 18 minutes" can generate the sequence "in the next CD NN " and " IN DT JJ 18 minutes," but the constituents CD in the former case and DT and JJ in the latter case are not necessary in all situations.