- You had better consult a doctor.
- It is late. I had better hurry up.
Had better may suggest a threat. It is not used in polite requests.
- Could you lend me some money? (request)
- You had better lend me some money. (order/threat)
Had better refers to the immediate future, but the form used is always past. Have better is not possible.
- Shall I go now? You had better. (NOT You have better.)
We can put better before had for emphasis. This is common in British English.
- ‘I promise I will pay you back.’ ‘You better had.’
We normally make the negative with had better not + infinitive.
- You had better not tell him.