This wikiHow teaches you how to change the keyboard input language on a Mac.
Step
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Step 1. Click the Apple menu and select System Preferences…
It's a black apple icon in the upper-left corner of the screen.
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Step 2. Click the Keyboard option
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Step 3. Select the Input Sources tab at the top of the dialog box
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Step 4. Click the option which is at the bottom left pane of the dialog box
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Step 5. Click the desired language
The available languages are displayed alphabetically.
Keyboard input languages that have been added will appear at the top of the list
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Step 6. Click the desired keyboard/input style for the corresponding language
The input style will be displayed in the left pane of the dialog box.
An example of a keyboard layout will be displayed at the bottom right of the screen when you click on an input source
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Step 7. Click the Add button
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Step 8. Check the "Show Input menu in menu bar" option at the bottom of the dialog box
After that, a flag icon will be displayed on the right side of the menu bar.
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