None of the attempts to specify the causes of crime explains why most of the people exposed to the alleged causes do not commit crimes and, conversely, why so many of those not so exposed have.
27 None of the attempts to specify the causes of crime explains why most of the people exposed to the alleged causes do not commit crimes and, conversely, why so many of those not so exposed have
og里给的解释是,这句话将“why most of the people exposed to the alleged causes"和”why so many of those not so exposed"这两种人比较。所以为了保持比较中的平行,两部分的动词也要平行。前面的动词是”do not commit“,所以后面也跟一般现在时的。