How to use も (mo) correctly
“Mo” indicating addion is equivalent to “too”, “as well” and “also”. I think it’s not hard to understand its meaning, but it seems that the usage of “mo” in Japanese is a little different from these English words. In English they come at the end of the cluase or before the main verb, but “mo” does not. When non-Japanese use “mo”, they sometimes add it at the end of the sentence like “too” and “as well”. However this is not correct.
Here are the usage rules of “mo”. Please pay attention to the location of “mo”.
1) Additional noun + “mo”
Yamada: watashi wa opera ga suki desu. (I like opera.)
Tanaka: watashi mo. (Me, too)
2) “Mo” replaces “wa”, “ga”, and “o”.
John wa Paris ni itta. Watashi wa itta. (John went to Paris. I did.)
>> John wa Paris ni itta. Watashi mo itta. (John went to Paris. I did, too.)
*”i”, in addition to other people (John)
Maiasa mizu o nomu. coffee o nomu. (I drink water every morning. I drink coffee.)
>> Maiasa mizu o nomu. Coffee mo nomu. (I drink water every moring. I also drink coffee.)
3) “Mo” does not replace “ni” and “de”. They remain and “mo” is added.
Watashi wa London ni itta. Paris ni mo itta. (I went to London. I went to Paris, too.)
Hokkaido ni hikouki de iku? Densha de mo ikeru yo. (Are you going to Hokkaido by plane? You can go there by train, too.)
4) Adjective + “mo” is not possible.
[incorrect] Tanaka san wa wakakute, okanemochi de, kakkoii mo??? (Tanaka is young, rich and also handsome.)
[correct] Tanaka san wa wakakute, okanemochi desu. Sore ni, kakkoii desu. (Tanaka is young and rich. In addition, he is handsome.)
5) “Mo” can be used in a negative sentence.
Sato: Watashi wa osake ga suki janai. (I don’ like alcohol.)
Suzuki: Watashi mo. (Neither do I.)
For your information, it’s hard to hear the difference between “mo” (も) and “mou” (もう), but they are completely different words. Keep this in mind!