it's good ...后面加for 还是of?

it's good ...后面加for 还是of? It's good for 和 It's good of有什么区别,后面接的是sb It's time for 后面加什么? it's good of you to do sth还是it's good for you to do sth it is good of还是for you, It was from a good friend of his 后面是填 mother's 还是 mother It's time for后面加动词原形还是动词ing形式? it's good for It's good for us to eat a lot of ( ) (vegetable),要不要加S的 ,为什么 it's kind . 用for 还是of it's time for后面人称怎么加 She said it's good for you.中的it's是it is 还是it was,