machine-readable submenu items
In this case You can use Accessibility Inspector which is part of the Xcode Developer Tools package (simply install Xcode).

To launch it use Spotlight (⌘ cmd+space bar) and type "Accessibility Inspector". Then turn on inspection pointer with ⌥ alt+space bar, open your contextual menu, point on the item you want to inspect and press ⌥ alt+space bar to lock it again. You'll have all informations about element such as Title, Frame, Type etc. (you can copy paste them to translator if you want)