> 明快な口調とテンポの良い楽しい授業が時の経つのも忘れさせる。

Ｗhen I searched the Internet I found the phrase `時の経つのを忘れさせる`.

So, what is the reason for replacing the particle を with も?
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2019-11-24T18:37:30.320
73218
2019-11-25T08:35:54.770
2019-11-25T08:35:54.770
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question
grammar particles particle-も
Omitting the particle? 「時の経つのも忘れさせる」
Unlike English "also", the particle も can be used when there is no explicit
"similar" thing specified in the context. In such cases, も is closer to
"even". Either way, the basic rule is も **replaces** を (and が, は).

>   * 笑っている人もいた。 There are even laughing people.
>   * 天才もミスをする。 Even a genius makes mistakes.
>   * 時が経つのを忘れた。 I forgot about the (passage of) time.
>   * 時が経つの **も** 忘れた。 I forgot _even_ about the (passage of) time.
>

Keeping を and saying 時が経つの **をも** 忘れさせる is actually grammatical, too, but it
sounds fairly stilted. See:

  * [をも: Is this sentence grammatically correct?](https://japanese.stackexchange.com/q/30945/5010)
  * [をも.... what on earth is this particle combination?](https://japanese.stackexchange.com/q/13405/5010)
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2019-11-25T05:13:14.773
73228
2019-11-25T05:13:14.773
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73218
answer