Stumble upon and Take form

Stumble upon verb - To come upon face-to-face or as if face-to-face.

Take form and stumble upon are semantically related. In some cases you can use "Take form" instead a verb "Stumble upon".

Take form verb - Develop into a distinctive entity.

Stumble upon and take form are semantically related. Sometimes you can use "Stumble upon" instead a verb phrase "Take form".