—I am trying my best to learn English, but it doesn’t work well!—Don’t worry! Regard it _____ a big challenge!
This problem is so tough that they can’t find the ____.
________! Said the teacher angrily.
—Did Sam go to the cinema yesterday? —Yes, we all went there ____ him.
He is sitting _______ the room that is _________ the old tree.
The doctor told me to take this medicine ____.