1)how, students, parasites, to use, are taught, measures, to kill, effective.
2) problematic, pollution, concerns, the, with, most, environmental, deal, production, and.
3) everyone, everything, in, power, nature, it, very, that, is, do, important, his, to, must, preserve.
4) are, pairs, in, the, vertebrae, arranged, ribs, in, thoracic, which, correspond, number, to.