Sorry, I didn't get that part. Could you read it again please?
These are two wonderful examples because first of all "Would you mind repeating that part again please?" uses the word "repeating" which is essential for your teacher to asses the part that you didn't catch.
Also "Sorry, I didn't get that part. Could you read it again please?" has the word "get" which has the same meaning as "catch". Children in school often say "Teacher I don't get it" to express that they don't understand something.
これら２つは素晴らしい例といえます。
"These are two wonderful examples because first of all "
"Would you mind repeating that part again please?""
""repeating""を使って、聞き取れなかった部分を先生に判断してもらうこともできます。
また、 ""Sorry, I didn't get that part. Could you read it again please?"" には ""get"" あってっていて、これは、 ""catch""と同義です。
子どもは""Teacher I don't get it""と聞き取れなかったり、理解できなかった時に使います。
Could you come again with that last sentence please?
Would you please say that last part again? I didn't quite catch it.
Sorry, would you please repeat that last part to help my understanding?
To catch something = to understand something
"Henry didn't catch the meaning of the toilet signs and walked into the ladies!"
To come again = To say again
A "My house is painted XXXX."
B "Come again? What colour?"
A "Blue."
To catch something =理解する
"Henry didn't catch the meaning of the toilet signs and walked into the ladies!"
「ヘンリーはトイレの看板の意味を理解しておらず、女子トイレの中に入った！」
To come again=もう一度言う
A:私の家はXXXX色で塗装されています
B もう一度言って？どんな色ですか？
A:青です。
「聞き取れない」は、ニュアンスによっていろいろあります。
たとえば、「音そのものが（例えば小さすぎてとかで）聞き取れない」なら
inaudible
hard to hear
などです。が、このご質問のニュアンスの場合ですと、
「音をキャッチできない」という意図での使い方になりますので
catch を使うのがよろしいかと思います。
Could you read the parts that I couldn't catch?
「私が聞き取れなかった部分を読んでくれますか？」
that以下はpartsを後ろから説明している関係詞節になります。
ご参考になれば幸いです。
Teacher D, Can you please read the second paragraph again. I did not hear properly.
>Teacher D, Can you please read the second paragraph again. I did not hear properly.
Referring the the section (paragraph 2) helps the teacher to know what he must repeat.
Teacher D, Can you please read the second paragraph again. I did not hear properly.
第2段落を参照することでどの部分を繰り返さなければならないか先生が知ることができます。
Please repeat that part again
means : please say that again
You can also say : 'I don't understand, please repeat that again.
'Please read that part again, I don't understand it.'
Please repeat that part again.
これは、「もう一度言ってください」という意味です。
また、'I don't understand, please repeat that again.'
（わかりません。もう一度言ってください。）ということもできます。
'Please read that part again, I don't understand it.'
（もういちどこの部分を読んでください。よくわかりません。）
I couldn't hear that bit can you repeat it for me please?
If you want to ask someone to do something for you then you can ask 'can you' or 'would you'
if you are asking someone to do the same thing again this is called 'repeating' or to 'repeat'
by adding 'I couldn't hear that bit' this explains why you want them to read it again/repeat it
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