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 Documentation / Mathematica / Other Information / 2D Expression Input / Editing 2D Expressions  /
Selecting the next-higher subexpression

Select the next-higher subexpression by pressing the Control key and the Dot key (the "." key) at the same time.

Press. repeatedly

Deleting to destructure an expression

Get rid of the contents of an expression and destructure it by pressing the Backspace key (Delete key on some systems).

Backspace repeatedly

Another example:

Backspace repeatedly