Don't let those who are not old enough▁▁the video game arcade.(enter)

Don't let those who are not old enough▁▁the video game arcade.(enter)
Don't let those who are not old enough▁▁the video game arcade.(enter)

Don't let those who are not old enough▁▁the video game arcade.(enter)
enter
those who are not old enough是宾语,用了一个定语从句,那些年纪不够大的人
因此主干是：Don't let ...do ..,让谁做某事,不带to的动词不定式即动词原形

Don't let those who are not old enough▁enter▁the video game arcade.(enter)