4.【名次单数不能单独做主语】错误语法:【Seat belt is the best way to reduce the severity of injuries.】正确语法:【Seat belt are the best way to reduce the severity of injuries.】。
5.【动词原形不能单独做主语】错误语法:【Work at home using modern technology can guretly enhance our efficiency.】正确语法:【Working at home using modern technology can guretly enhance our efficiency.】。