Standing on the platform, Professor Li kept silent for a moment, on the audience below.
---Where does he come from ? --- Pardon? --- I asked where_________. A…. did he come from B. he came from
She wondered __________.
---Do you know ________? --- I'm not sure. Maybe he is a businessman.
He is a friend ______ can help you in time of need.
The most important thing ______ we should pay attention to is the first thing ______ I have said.