I'm surprised that you should have been fooled by such a(an)___trick
We already have ______pencils, but we need two ____ pens.
Why are you leaving right now? You promised to stay ____ hours.
We asked John and Jerry, but ____ of them could offer a satisfactory explanation.
This book______18 articles , _______ three written by my father.
Chest pains can be a warning ____of heart problems.