21. Carl is studying food science at college and hopes to open up meat processing factory of his own one day.
A. / ; a B. / ;the C. the; a D. the; the
22.——May I help you? You seem to be having some problems.
—— , thanks. I think I can manage.
A. All right B. No problem C. It’s all right D. There’s no way
23. Interest is as to learning as the ability to understand, even more so.
A. vital B. available C. specific D. similar