Work hard at your lessons, ______ you’ll fail the exams again.
A．and B．but C．or D．which
He devoted all the time _____ his research .
A．to do B．doing C．to doing D．did
Mr. Liu dreamed ____ a big house for his parents after they retire.
A．to buy B．to buying C．of buying D．of being buying
On the bus I saw a student____ I thought was your brother.
A．who B．whom C．which D．/
We’ll never forget the days ______ we lived in the country.
A．when B．where C．which D．/
He lives in a room _______ faces the south.
A．whose windows B．the window of which
C．whose the window D．of which the windows
