Explanation
Use "had better" to give strong advice or a warning. It usually means "it is a good idea to do this now". The word "had" does not mean past time here.
In "You had better take an umbrella.", "You" is the person, "had better" is the fixed grammar, and "take" is the base verb. In Japanese, this is often "傘を持っていったほうがいい". Use "had better not" for negative advice.
"had better" は、強い助言や注意を言うときに使います。だいたい「今それをしたほうがいい」という意味です。ここでの "had" は過去ではありません。
"You had better take an umbrella." では、"You" が相手、"had better" が決まった形、"take" が動詞の原形です。日本語では「傘を持っていったほうがいい」に近いです。否定は "had better not" を使います。
Examples
- You had better call your mother tonight. 今夜、お母さんに電話したほうがいいよ。
- We'd better leave now. もう出たほうがいい。
- You'd better get to bed now or your mom will get upset! もう寝ないと、お母さんが怒るよ！
- You had better not be late. 遅れないほうがいいよ。
- She'd better see a doctor. 彼女は病院へ行ったほうがいい。
- You'd better finish your homework if you want to watch TV later. 後でテレビを見たいなら、宿題を終わらせた方がいいよ。
Common Mistakes
Japanese learners often write "You better go" or "You had better to go". The correct form is "You had better go". Do not add "to" after "better", and do not drop "had" in standard English.
日本人学習者は "You better go" や "You had better to go" と書きがちです。正しくは "You had better go" です。"better" の後ろに "to" はつけません。また、標準英語では "had" も必要です。