to nuclear radiation, even for a short time, may produce variants(变异)of genes in human bodies.[ ]

Unlike watching TV, reading is a highly active process________it requires attention as well as memory and imagination[ ]

Do you have a new watch— No, I _________ .

ese changes willlead to stronger China, countrythat can surprise and enrich our planet

Don’t play with the knife, _______ you’ll cut yourself.—-Sorry, I_________ .