you'd better后面加动词的原形。you'd better全拼为you had better，中文翻译为“你最好”、“你最好脱掉你的外套”、“一定来啊”，后面接不带to的不定式，构成you had better do sth句型，意为你最好做某事。
youd better加动词是什么形式
you'd better即you had better后面加动词原型 (即不带to的不定式)，构成you had better do sth.句型。意思是"你最好做某事”。
better英 [ˈbetə(r)] 美 [ˈbɛtɚ] ；adj.较好的;更合适的;能力更强的;好转的。
adv.更好地;更;更妥；v.胜过;上进；n.更好者;更有才智者。
第三人称单数： betters 复数： betters现在分词： bettering过去式： bettered .过去分词： bettered.
had better do sth. 最好做某事。这是固定搭配, 适用于各种人称和数。had可与主语缩写也可不缩写。
youd better的双语例句有哪些
You'd better study harder if you want to pass the exam.
（如果你想通过考试，最好努力学习。）
You'd better not eat too much junk food. It's bad for your health.
（你最好不要吃太多垃圾食品，对健康有害。）
You'd better hurry up, or you'll be late for the meeting.
（你最好赶紧，否则会迟到开会。）
You'd better check the weather forecast before heading out.
（出门前最好查一下天气预报。）
You'd better be careful when crossing the street.
（过马路时最好小心点。）