Onomatopoeia for the sound effect associated with a correct answer. / Onomatopoeia for the doorbell ringing.

(informal) doorbell

a house / one's own home / a home, household / a family

the wave dash: 〜

Spread of infection, such as a cold or sexually transmitted infection, amongst members living together.

ping pong ball

child's naive mind, child's juvenile mind

plural of 子供: children

a house

house of something, place where some business is conducted / person who does that thing