She is a helpful girl.
The teacher gave us a lot of helpful books in maths.
It was a helpful thing to do.
You've been very helpful.
She is intelligent, outgoing and helpful.
The book is really helpful, don't you think?
I always think criticism is helpful.
S+be+～+ prep .-phrase
He is always very helpful to his mother.
This dictionary is very helpful to your English study.
It's helpful to us.
It is/was+～+for〔of〕 sb+to- v
Don't throw it, it is helpful for us to repair the bike.
It was helpful of you to do that.
You may find this book helpful.