Volitional Form: Let's / I'll / Shall We
Quick Answer: Group 1: change u-sound to o-sound + う (行く→行こう). Group 2: drop る→よう (食べる→食べよう). Irregular: する→しよう, 来る→来よう. Polite: ましょう.
Expressing intention and making suggestions
Category: Verb Forms
The Rule
Group 1: change u-sound to o-sound + う (行く→行こう). Group 2: drop る→よう (食べる→食べよう). Irregular: する→しよう, 来る→来よう. Polite: ましょう. Used for suggestions ('let's'), intentions ('I'll'), and volitional patterns (〜ようとする = try to).
Why This Matters
The volitional form maps loosely to English 'let's' and 'shall we,' but it also expresses personal intention ('I think I'll...'). English speakers should note: the plain volitional (行こう) is casual, while ましょう is polite. Using the wrong level sounds odd.
Examples
• 一緒に食べましょう。 — "Let's eat together." [Polite suggestion: ましょう] • そろそろ帰ろう。 — "Let's head home soon." [Casual suggestion: 帰る → 帰ろう] • 日本語を勉強しようと思います。 — "I'm thinking of studying Japanese." [〜ようと思う = 'I think I will'] • 何度も説明しようとしたが、分かってもらえなかった。 — "I tried to explain many times but couldn't be understood." [〜ようとする = 'try to do']
Common Mistakes
❌ 行くう ✅ 行こう → Group 1: change to o-row + う. 行く → 行こう (く→こ+う), not 行くう ❌ 食べろう ✅ 食べよう → Group 2: drop る, add よう. Don't mix up volitional (よう) with imperative (ろ)
Quick Tip
ましょうか (with か) turns a suggestion into a polite offer: 手伝いましょうか = 'Shall I help?' Without か, it's a group suggestion: 手伝いましょう = 'Let's help.'
ましょうか (with か) turns a suggestion into a polite offer: 手伝いましょうか = 'Shall I help?' Without か, it's a group suggestion: 手伝いましょう = 'Let's help.'
Examples
Common Mistakes
Incorrect: 行くう → Correct: 行こう. Group 1: change to o-row + う. 行く → 行こう (く→こ+う), not 行くう
Incorrect: 食べろう → Correct: 食べよう. Group 2: drop る, add よう. Don't mix up volitional (よう) with imperative (ろ)
Quiz
How do you say 'Let's do it!' (casual)?