可以 vs 能 vs 能够

可以 (kěyǐ), 能 (néng), and 能够 (nénggòu), all the three words all translate to "can" or "be able to" in English, but they have different nuances and usage rules in Chinese. Here's a clear breakdown:

1. 可以 (kěyǐ) – "May / Allowed To" (Permission & Possibility)

Meaning & Usage:

• Permission: Asking for or granting permission (like "may" in English).
  • ✅ "你可以进来。" (Nǐ kěyǐ jìnlái.) – "You may come in."
  • ✅ "这里可以停车吗？" (Zhèlǐ kěyǐ tíngchē ma?) – "Can I park here?"
• Possibility (objective): When something is possible due to circumstances.
  • ✅ "这个房间可以住两个人。" (Zhège fángjiān kěyǐ zhù liǎng gè rén.) – "This room can accommodate two people."
• Suggestion / Advice: Offering a suggestion.
  • ✅ "你可以试试这个方法。" (Nǐ kěyǐ shìshi zhège fāngfǎ.) – "You can try this method."

Negation: 不可以 (bù kěyǐ) – "Not allowed / May not"

• ❌ "这里不可以吸烟。" (Zhèlǐ bù kěyǐ xīyān.) – "You may not smoke here."

2. 能 (néng) – "Can / Able To" (Ability & Capability)

Meaning & Usage:

• Ability (innate or learned):
  • ✅ "他能说三种语言。" (Tā néng shuō sān zhǒng yǔyán.) – "He can speak three languages."
• Physical capability (strength, health, etc.):
  • ✅ "我病了，不能工作。" (Wǒ bìngle, bù néng gōngzuò.) – "I'm sick and can't work."
• Circumstantial possibility (external factors):
  • ✅ "今天下雨，我们不能去公园。" (Jīntiān xiàyǔ, wǒmen bù néng qù gōngyuán.) – "It's raining today, so we can't go to the park."

Negation: 不能 (bù néng) – "Cannot / Unable to"

• ❌ "你不能在这里停车。" (Nǐ bù néng zài zhèlǐ tíngchē.) – "You can't park here."

3. 能够 (nénggòu) – "Be Capable Of" (Formal Ability)

Meaning & Usage:

• Formal ability (often written or official contexts)
  • ✅ "他能够完成这个任务。" (Tā nénggòu wánchéng zhège rènwu.) – "He is capable of completing this task."
  • ✅ "人类能够登上月球。" (Rénlèi nénggòu dēng shàng yuèqiú.) – "Humans are capable of landing on the moon."
• Used in positive statements (rare in negative sentences)
  • ❌ "他不能够来。" (×) → Unnatural (use "他不能来。")

Negation: 不能够 (bù nénggòu) – Rare, usually replaced by 不能 (bù néng)

Comparison Table

Key Differences

Permission vs. Ability:

• 可以 (kěyǐ) → Permission ("may I?").
• 能 (néng) → Ability ("can I?").
• 能够 (nénggòu) → Formal ability (rare in speech).

Formality:

• 可以 & 能 → Used in daily speech.
• 能够 → Mostly in writing, reports, or formal speech.

Negation:

• 不可以 (bù kěyǐ) → "Not allowed."
• 不能 (bù néng) → "Cannot / Unable to."
• 不能够 (bù nénggòu) → Rarely used (usually replaced by 不能).

When to Use Which?

• Use 可以 when:
  • Asking for permission ("Can I...?").
  • Suggesting something ("You can try...").
• Use 能 when:
  • Talking about skills ("I can speak Chinese").
  • Referring to physical ability ("I can't run").
• Use 能够 when:
  • Writing formal reports ("He is capable of leading").