MacOS – Why keyboard shortcut “ctrl + left” doesn’t work

Go to System Preferences -> Keyboard -> Keyboard Shortcuts. Then, on the left side, select Exposé & Spaces. On the right side you will see the current keyboard shortcuts for Exposé and Spaces. If you double click on the shortcut command (literally double click ^1 for instance) you will be able to change this to whatever you want. Just do the key-combo you want to use.

So, once you double-click on the shortcut, it'll show it as editable. Then, press the keys you want the short cut to be, all at once, for instance press Apple and J at the same time, and it'll change the shortcut.

Yes, there are better approaches. Open:

System Preferences->Keyboard->Shortcuts

Highlight the App Shortcuts on left pane. You will see a list of apps on the right. Click the Plus sign and then select Eclipse for the app, type the menu item, type your new keyboard shortcut and you are done: