Why not to split on sentence level (or smaller)?
Professional translator tools sometimes split the document at the sentence level in order to maximize the reusability of previous translations and speed up their process. The problem is that the same sentence may have several translations, depending on the context. Paragraphs are by definition longer than sentences. It will hopefully ensure that having the same paragraph in two documents will have the same meaning (and translation), regardless of the context in each case. Splitting on smaller parts than the sentence would be very bad. It would be a bit long to explain why here, but interested reader can refer to the Locale::Maketext::TPJ13(3pm) man page (which comes with the Perl documentation), for example. To make short, each language has its specific syntactic rules, and there is no way to build sentences by aggregating parts of sentences working for all existing languages (or even for the 5 of the 10 most spoken ones, or even less).
