helpful       
adjective uk/ˈhelp.fəl/ us/ˈhelp.fəl/
B1 愿意帮忙的;有帮助的,有用的
willing to help, or useful
  She's such a pleasant, helpful child! 她可真是个招人喜欢又乐于助人的孩子! 
 I'm sorry, I was only trying to be helpful. 真抱歉,我只是想帮忙。 
 He made several helpful suggestions. 他提了几条很有帮助的建议。 
 - More examples
 - Students said it was helpful if the teacher corrected their pronunciation.
 - Any increase in production would be helpful.
 - You get the odd person who's rude to you but they're generally quite helpful.
 - You should find this guidebook helpful.
 - She made some very helpful suggestions but her boss rejected them all.