You can temporarily change the interface language to English by clicking the globe icon at the top left and then selecting "English". The language will change back to English once you log out.
Follow there instructions to permanently change the user interface default language:
1.Click on your name at the top left corner of the screen and then select "Preferences".
2. Select the option ""Preferred language" under the header "preferences".
3. Change the preferred language to English and press the save changes button.