一个英语问题：是They are helpful for me还是They are helpful to me

一个英语问题：是They are helpful for me还是They are helpful to me they are a( ) polite and helpful In this wzy they are more helpful to us than many other还是 ot thank you for s_____ for good eating habbit.they are helpful They are all nice and helpful to each other.(改为同义句) they are all nice helpful to each other.(改成同意句） they are kind,helpful and pleasant to get acquainted with.该怎 These are not my sweater .They are( )big for me 对某人有用是be helpful to sb.还是be helpful for sb? Our students are very good and they are polite and helpful一句 you are helpful是什么意思 Jim wih his good friends ____(be)helpful.They often help me