Use both Macbook and external display
Effect: the screen of the Macbook is the same as that of the original one. The external large display is the main screen. The macbook is a secondary screen that only displays desktop images, without the Dock and the status bar above.
Implementation Method: Open the Display setting interface in System Preferences (System Preferences) in the drop-down menu of the Apple logo in the upper left corner. Click the Detect Displays button. The external display will respond unexpectedly. You can check the "Show Display in menu bar" check box below to Display a TV icon in the desktop Menu bar, to set any settings for the dual-display, click it to find the desired settings.
The screen of the Macbook does not work. You can only use the external big monitor www.2cto.com. You can use the Macbook as a computer host, connect the mouse and keyboard, close the Macbook, and turn the external monitor into an iMac.
Implementation Method: first achieve the above dual screen effect, move the mouse to the external LCD display, then close the Macbook, enter the sleep state. How about a few mouse clicks? The external monitor woke up and the screen of the Macbook was still asleep.