Shuā / yá / shí / yào / zǐ / xì / qīng / jié / shàng / qiāng / bì / miǎn / shí / wù / cán / liú刷牙时要仔细清洁上腔,避免食物残留。When brushing your teeth, clean your upper gums carefully to prevent food from remaining there.