I had a little trouble       English grammar.

I’m new at the party and I don’t have a friend ____.

Jane is so shy that she is afraid of       in front of a group.

---What a heavy rain!
----So it is. I prefer ______ at home ______on such a rainy day.

--- You look ______,Paul. What’s the matter?--- I’m having trouble ______ math.

My funny joke made my grandparents ___ happy.

Thanks a lot for _______me _______your party.  
A invite ,for    B. invite ,to          C. inviting ,to D. inviting ,for

-Is Sally from America?- Let me ________.

His brother is only six years old. He has difficulty       the story books.

Do you mind        the door?