Click on the globe icon next to the save icon on the top to the left, and select whichever language you'd like (in this case English) from the list.
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Changing the language is quite simple. All you need to do is click the globe like shape at the top in between the Scratch logo and the save button (Not the "file" button, don't get those two mixed up.). Click it, and select English.
Then, your Scratch should be in English.
Hope this helped!
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