They seemed ______ each other for a long time.
A．knowing B．to know C．having known D．to have known
This is Mr. Smith. _______ help I worked out many difficult problems.
A．whose B．with whom C．who D．with whose
---I’d like to buy a new computer.
---Well, we have several models __________.
A．to choose from B．to choose
C．for choosing D．for choice
_______ to take this advance course will certainly learn a lot of useful skills.
A．Brave enough students B．Enough brave students
C．Students brave enough D．Students enough brave
We all made him ________ head of our class.
A．the B．a C．one D．/
As we joined the big crowd I got _________ from my friends.
A. separated B. spared C. lost D. missed
