One of the best navigation pattern for responsive design when it comes to multilevel menus is presenting them a way that is less confusing and more appealing for Mobile Users. If you have huge drop-down menus with lots of pages in your navigation, then the best approach is to turn them into an accordion-toggle like structure on smaller screen viewports / devices!
Hiding some of your navigation menu items may sometimes not be an option, it can give your website visitors crappy User Experience (UX), the kind that is similar to cheating mobile devices and tablets. To make the mobile user experience a breeze and memorable, give your Website visitors the full menu items without altering your main menu structure, their fingers will smile on single TAP, the rest will be history, and hey - you may thank me later!