Grammar · N4
Modality Part 1: でしょう vs かもしれません
「でしょう」と「かもしれません」の違い
By Can-sensei ·
みなさん、おはようございます！ Today, I'd like to share the differences between 「でしょう」 and 「かもしれません」. If you are using Minna no Nihongo, this is taught in Lesson 32.
In real life, both are very commonly used, especially when you are talking about whether you or someone will go to a party. Consider the following conversation.
会話1 — talking about yourself
A: 明日、学校でパーティーがあるそうですが、行きますか。
A: I heard there's a party at school tomorrow. Are you going?
B: まだわかりません。行くかもしれません。
B: I don't know yet. I might go.
If you were to replace 「かもしれません」 with 「でしょう」, it would sound funny, because 「でしょう」 is usually used on others, not on yourself.
会話2 — talking about someone else
A: 明日、学校でパーティーがあるそうです、Jasonさんは行きますか。
A: I heard there's a party at school tomorrow. Is Jason going?
B: 彼は行くでしょう。彼女のCeciliaさんも行きますから。
B: He'll probably go. His girlfriend Cecilia is going too.
In this context, it would be ok to use 「でしょう」 as it is talking about Jason, instead of Bさん himself.
Softening and avoiding assertion
Both 「でしょう」 and 「かもしれません」 can be used to avoid assertion and to soften the sentence.
天気予報によると、明日雨が降るでしょう。
According to the weather forecast, it may rain tomorrow.
間違っているかもしれませんが、あなたはTampinesに住んでいる田中さんですか？
I may be wrong, but are you Tanaka-san who lives in Tampines?
Take note: 「かもしれません」 cannot be used as a question. ✗ 今晩雨が降るかもしれませんか。
References: 初級日本語文法と教え方のポイント; 改訂版日本語文型辞典.