预防: to prevent, to take precautions against, to protect, to guard against, precautionary, prophylactic...
身边: at one's side, on hand...
前提: premise, precondition, prerequisite...
推敲: to think over...
取决于: to hinge on, to be decided by, to depend on...
遗传: heredity, to inherit (a trait), to pass on (to one's offspring)...
忧虑: to worry, anxiety (about)...
蹭: to rub against, to walk slowly, (coll.) to freeload...
苍蝇: housefly...
信封: envelope...
