1) Yu! That child/kid is drowning! Sign: Yukkuri pool *puka puka* [bobbing sound]
2) Eh- no no, it's not drowning, see it's smiling Yu-! That child/kid just naturally has a face like that! It looks like it's really struggling painfully! *puka puka* [bobbing sound]
3) It doesn't look like that at all it's not drowning Yu~n it's drowning! Pyiiii-!! *jaba jaba* [wading, splashing sound]
4) Hey you! Don't fool around and pretend to be drowning! Yesh!?
it's pointless putting this on a 6 year old post but "hyui" is actually something Nitori cries out in subterranean animism and it doesn't mean "yes" at all