• When you move the mouse pointer over the cell with the comment, it will show.
• Insert a Comment in a Cell
• Choose the appropriate cell.
• Click the New Comment button on the Review tab:
• Begin composing your remark in the yellow box that appears:
• When you're finished, simply click away from the comment.
• As you can see, the red triangle has appeared in cell E4, indicating that a comment has been successfully created in that cell.

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