The 副助詞(ふくじょし) (adverbial particle)
も is often used for labeling (A) as part of a category, when it would not usually be considered part of that group. In this way, it emphasizes that (A)’s inclusion is something that is surprising/unexpected in some way.
When
も is used after a specific number + counter, it shows that the number itself is surprising. This can be when the actual number is lower, or higher than what was expected. Due to this,
も can translate as ‘as much as (A)’, or ‘not even (A)’, and other similar phrases in this expression.
-
12時間(じかん)も仕事(しごと)をしたから疲(つか)れた。
I worked as long as 12 hours, so I am tired.
-
その携帯(けいたい)20万円(まんえん)もしたの?!
That cellphone cost you as much as 200,000 yen?!
-
私(わたし)は一回(いっかい)も地下鉄(ちかてつ)に乗(の)ったことが無(な)い。
I have never taken the subway, not even once.
At first glance, this may seem different than
も’s translation as ‘too’ or ‘also’, but in those cases,
も is also just pointing out the something unexpected is part or whatever group was initially highlighted.
-
私(わたし)も行(い)きたい。
I want to go too.
The above sentence just shows that the (B) speaker is unexpectedly putting themselves in the group that the (A) speaker initially only considered themselves to be a part of.