It’s+形容词+for sb.+to do sth.

It's nice for you to help me.

It's happy for you to invent me.

It's difficult for me to work up this promblem.
对我来说，要想解决这道题很难。

It's easy for Lily to answer this question.
对莉莉而言，这道题很容易回答

It's healthy for elders to take walks every day.
It's good for young people to see more of the world.
It's unhealthy for animals to be locked up all the time.

It's impossible for you to pass the exam

it's difficult for me to work this maths problem out.

it's happy for me to see you in my birthday.

lt's nice of you to say so.你这样说真是太好了
lt's selfish of Jim to eat the whole birthday cake.吉姆真自私，吃完了真个生日蛋糕