Parents had better not give kids more money than is necessary里面为什么用had 而不是用have

Parents had better not give kids more money than is necessary里面为什么用had 而不是用have had better/would better区别? Parents had better not give kids more money than what is needed.帮忙分析一下语法成分 谢谢 you had better make had better do=? 英语 翻译 had better had better 同义短语 you had better would better和had better一样吗? had better和would better的区别 would better 和had better的区别? should better与had better的区别 had better 这里为什么是用had 是had better to do还是had better do had better do还是had better to do had better=?had better=什麼单词 had better +do sth 还是had better +to do sth 请问 had better not = had better no