---Where is our English teacher?---She is in the classroom, _______ the exercises _______ the students have done at home.
Between the two generations, it is often not their age, _________ their education that causes misunderstanding.
I tried phoning her office, but I couldn’t-----------
I smell something __________ in the kitchen. Can I call you back in a minute?
We all know that, __________, the situation will get worse.
—Have you known Dr. Jackson for a long time? —Yes, since she ______ the Chinese Society.