WHOLE CHARACTER
兴xīng, xìng
to start; to establish (兴办, 兴建); to rise; to flourish (兴旺, 兴盛); to be popular (时兴, 新兴); maybe; perhaps (兴许)
兴 read xīng starts and builds things up; read xìng it is the mood you enjoy.
The modern form is shown completely: a three-dot top over the bar and the radical 八. ZDIC says the formation was originally 会意 for the older 興.
TOP THREE-DOT PIECE
⺍
Notice this part of the shape; it is not taught as a separate word in this lesson.
In 兴: top three-dot piece Shown with its documented or clearly limited role.
MIDDLE BAR PIECE
一yī
one
Structural source piece in 百; not every visible stroke-like piece is taught as a separate word.
In 兴: middle bar piece Shown with its documented or clearly limited role.
BOTTOM PIECE (THE RADICAL 八)
八bā
eight
Standalone meaning is kept separate from its role in other characters.
In 兴: bottom piece (the radical 八) ZDIC lists 八 as the radical.