If you are free to walk through out city, please ________ us.A drop in B drop in at C. drop in on
—Forgotten something ? I can look after your kids if you want to go and get it. —_________. Thank you all the same.
It _____that this method didn't work well.
There is a hole _____ the wall. The wind is blowing in ______the hole.
His grandfather joined the Party in _______and passed away in ______.
—You _______be excited that you are going to get the award. — I can't wait for it.