Microsoft office tip:

Draw a perfect square or circle

Click on the Rectangle or Oval button on the Drawing toolbar. (If necessary, click Customize on the Tools menu, and then click the Drawing check box on the Toolbars to display the toolbar.)
Press and hold down both the [SHIFT] key and the mouse button.
Drag the mouse pointer diagonally downward and to the right until the rectangle or circle drawn has your preferred measurements.
Release the mouse button.
Release the [SHIFT] key.
In short, simply hold down the SHIFT key while dragging the mouse pointer!

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