Expressions (phrases, clauses, etc.), I-adjective (yoi/ii class)
had better ...
after past tense verb
薬箱は子供の手の届かない所に置いとく方がいいよ。You should keep the medicine box away from your child. had better not ...
after negative verbsee した方がいい
Also written 方が良い【ほうがいい】、ほうが良い【ほうがいい】、方がよい【ほうがよい】