伸 is built from the 亻 (person (left)) and 申 components.
It reads シン like 申, as do 神, 請, and 紳 — learn 申 once and the family's reading comes with it.
A common word using 伸 is 伸ばす (のばす), meaning “to extend, to stretch, to reach out”.
Don't confuse it with 申, 神, and 紳.
