peng1
impulsive

strokes 8
radical
strokes after radical 5
怦怦 怦怦 peng1 peng1
thumping sound (onom.); to be eager and anxious (to do sth); faithful and upright

怦然 怦然 peng1 ran2
with a sudden shock, bang etc

怦然心动 怦然心動 peng1 ran2 xin1 dong4
palpitating with eagerness to do sth (idiom)

心怦怦跳 心怦怦跳 xin1 peng1 peng1 tiao4
The heart thumps wildly. (idiom)