Here is the sentence.
新聞での寄付金詐欺をやったとき十万円もの大金を寄付した人がいただろう。
Removing them, does the meaning of the sentence change as much?
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Sign up to join this communityHere is the sentence.
新聞での寄付金詐欺をやったとき十万円もの大金を寄付した人がいただろう。
Removing them, does the meaning of the sentence change as much?
Can I omit「の」?
Yes. If you do so, the sentence structure (← grammar) will change but the meaning will be retained almost completely.
「[新聞]{しんぶん}での[寄付金詐欺]{きふきんさぎ}をやったとき、[十万円]{じゅうまんえん}もの[大金]{たいきん}を[寄付]{きふ}した人がいただろう。」
Here, 「新聞での」 modifies 「寄付金詐欺」. 「新聞での」functions adjectivally.
「新聞で寄付金詐欺をやったとき、十万円もの大金を寄付した人がいただろう。」
In this sentence, 「新聞で」 modifies 「やった」. 「新聞で」 functions adverbially.
Both sentences are grammatical and natural-sounding. They practically have the same meaning as well.
Can I omit「もの」?
No. You cannot omit the 「もの」 in 「十万円もの大金」 because you cannot say 「十万円大金」. If you used 「という」 instead of 「もの」, it would at least be a grammatical phrase, but 「もの」 will express the surprise much better.
***For learners interested in pitch accents, this 「もの」 is pronounced differently than 「もの」 meaning "thing". The pitch accent is on the 「も」 in this 「もの」. It is on the 「の」 in 「[物]{もの}」 and 「[者]{もの}」.