ふむふむhmmm, uh-huh, murmur indicating approval, comprehension, etc.

患者(かんじゃ)：「苦(くる)しい…。」医師(いし)：「ふむふむ、喘息(ぜんそく)かな？」

Patient: "It's painful..." Doctor: "Hmmm, could it be asthma?" {hmmm, uh-huh, murmur indicating approval, comprehension, etc.}

子供(こども)：「学校(がっこう)に行(い)きたくない。」大人(おとな)：「ふむふむ。理由(りゆう)は？」

Child: "I don't want to go to school." Adult: "Uh-huh. And why is that?" {hmmm, uh-huh, murmur indicating approval, comprehension, etc.}

娘(むすめ)：「私(わたし)の心(こころ)は男(おとこ)の子(こ)だと思(おも)う。」父(ちち)：「ふむふむ…そうだったのか。」

Daughter: "I think my heart is that of a boy." Father: "Uh-huh... Is that so?" {hmmm, uh-huh, murmur indicating approval, comprehension, etc.}

先生(せんせい)：「私(わたし)に見(み)せてごらん？ふむふむ…この言語(げんご)はスペイン語(ご)に違(ちが)いないね。」

Teacher: "Could you show me? Hmmm...This language is undoubtedly Spanish." {hmmm, uh-huh, murmur indicating approval, comprehension, etc.}

参考書(さんこうしょ)を読(よ)む時(とき)は「ふむふむ」や「なるほど」といった独(ひと)り言(ごと)がつい口(くち)から出(で)てしまう。

When I read reference books, murmurs like "hmm" and "I see" often slip out of my mouth. {hmmm, uh-huh, murmur indicating approval, comprehension, etc.}