The little girl tearfully told her mother about being bullied at school.

tearfully 是副词，由名词 tear（眼泪）加上形容词后缀 -ful（充满...的）构成形容词 tearful（含泪的、泪汪汪的），再加上副词后缀 -ly 构成。tearfully 表示"含着眼泪地、泪眼汪汪地"，用来描述说话时的状态。