The shortcut Ctrl+I is to italicize text or to remove italic formatting. You can also use shortcut Ctrl+3 or the Italic command from Home Tab, see here for details.
Step 1: Select the contents in the worksheet, e.g., A3:B4;
Step 2: Press and hold the "Ctrl" key and press "I" from the keyboard. You will find the data are italic now.
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