My deskmate is still a puzzle to me; at one moment he is quiet while at another he _____ be quite active.
The music ______ she is dancing sounds beautiful.
______ time ______, what the scientist said finally proved to be true.
Mary never does any reading in the evening, __________.
— Where is the panda? — It __________ by the doctor now.
I bought a vase of the Ming dynasty at such a low price at the Sunday market. It was really a nice __________.