sharpen vs change shape

sharpen and change shape both are verbs.

Word	Noun	Adjective	Verb	Adverb
sharpen	No	No	Yes	No
change shape	No	No	Yes	No

As verbs, change shape is a hypernym of sharpen; that is, change shape is a word with a broader meaning than sharpen:

Other hypernyms of sharpen include change form, deform.

sharpen (verb)	change shape (verb)
become sharp or sharper	assume a different shape or form
make crisp or more crisp and precise
raise the pitch of (musical notes)
put (an image) into focus
make (one's senses) more acute
give a point to
make sharp or sharper
make (images or sounds) sharp or sharper