问题
选择题
Food safety issues, ____ will seriously affect the growth of teenagers and even the nation’s future.
A．if not solved properly
B．not if solved properly
C．if solved properly
D．not if properly solved
答案
A
考查非谓语动词。根据句意，此处应为否定，排除C. 非谓语动词的否定词not应放在非谓语动词的前面，故排除B和D. 故A项正确。等于if they are not solved properly, ….。