I couldn't understand some parts of the listening content.
「聞き取れない」を英語で言うには"could not get"か"could not understand"が用いることが一般的です。音声のボリュームなどは「hear」や「listen」などの実際に「聞く」というニュアンスに対して、今回は「理解ができない」や「分からない」という日本語に置き換えることもできるので、そのような単語になります。
「テキストの一部」は英語でも"text"と言ってしまうと「文章」になってしまい曖昧な文になってしまうので、ここでは「contents（内容）」としました。
"I didn't get all of it" and "I couldn't understand some of it"
These expressions usually used when stating that you had not understood something completely, that you didn't understand everything, for example a recording.
To not 'get all of it', this is a causal and widely used expression and can be used in many contexts when not understanding or even collecting something.
"I didn't get all of it"
（全て聞き取れなかった。）
"I couldn't understand some of it"
（少し理解できなかった。）
これらは、例えば、音声などあるもののが完全に理解できなかったときに使うことができます。
To not 'get all of it'とは、カジュアルで広く使われている表現で、何かがわからなかったときに色々な場面で使うことのできる表現です。
I couldn't hear/understand clearly the part of the recording after the speaker said (In England...)
When you want to explain to your teacher that there's a certain part of a recording you did not hear/understand clearly; then you may express this in the following ways:
-I couldn't understand part of the recording
-I couldn't hear/understand clearly the part of the recording after the speaker said (In England...)
録音の一部が聞き取れなかったと先生に説明したいなら、次のように言えます。
-I couldn't understand part of the recording
「録音の一部が聞き取れませんでした」
-I couldn't hear/understand clearly the part of the recording after the speaker said (In England...)
「（イングランドでは...）の後の部分がよく聞き取れませんでした」
Some of the recording was garbled so I could not understand it.
I'm sorry I did not hear all of that.
I did not catch all of what was said.
Some of the recording was garbled so I could not understand it.
The message did not record clearly so I did not get the message.
I didn't understand the message because it was garbled.
I'm sorry I did not hear all of that.（すみません、聞き取れない所がありました）
I did not catch all of what was said.（聞き取れない所がありました）
Some of the recording was garbled so I could not understand it.（録音に不鮮明な所があったので理解できませんでした）
The message did not record clearly so I did not get the message.（録音が不鮮明だったので理解できませんでした）
I didn't understand the message because it was garbled.（不鮮明だったので理解できませんでした）
When listening to English learning material, you couldn't catch/understand a part of what the recording said. You can explain that you couldn't understand part of it by choosing one of the example statements above.
I'm sorry, I did not catch that part of the recording.
I did not understand this section of the recording. Could you please explain it to me?
Could you please replay that part of the recording, I did not understand the material.
"I'm sorry, I did not catch that part of the recording" - This statement shows that it was a mistake for not hearing the content being explained. This helps the person playing the material to repeat the section that you missed or did not hear.
"I did not understand this section of the recording. Could you please explain it to me?"- This statement shows you need a further explanation or different explanation of the material. By asking the question at the end it shows a clear indication that you need help with understanding the material.
"Could you please replay that part of the recording, I did not understand the material." - This statement informs the person playing the recording to please repeat the material in order for you to gain further understanding as it did not make sense to you.
"I'm sorry, I did not catch that part of the recording"（すみません、録音のその部分が聞き取れませんでした）
→この文は、聞き取れなかったことを「ミスであった」と表します。このように言うと、相手はもう一度聞き取れなかった部分を流してくれると思います。
"I did not understand this section of the recording. Could you please explain it to me?"（録音のこの部分が聞き取れませんでした。説明してもらえますか）
→ここでは、教材をさらに詳しくあるいは別の言い方で説明して欲しいと伝えています。最後の質問によって、その教材について相手に説明してもらいたいことが明確になります。
"Could you please replay that part of the recording, I did not understand the material."（録音のその部分をもう一度流してもらえますか。教材を理解できませんでした）
→ここでは、理解できなかったので録音をもう一度流してくださいとお願いしています。
日本 
イギリス 
南アフリカ 
アメリカ合衆国 
