How to undo error?

Hi I am very new to Blender. Just start to learn the basic functions. Currently I am learning how to use subdivide splits but split at the wrong edge.:confused: Please advice how can I undo the splits. Thanks

Regards,
Alice

Ctrl+Z is the hotkey for undo. If, however, you’ve saved and closed your .blend file before undoing your mistake, it shouldn’t be too difficult to fix. Are the vertices from your split in the same location as the ones that they originated from? If so, you may be able to just use W->Remove Doubles. Beyond that, it’s difficult to give suggestions without seeing a screenshot or the .blend file.

thanks ctrl+Z helps