—Who______ it be that is knocking at the door? —It ______ be Father, but I’m not sure.
The BRICS countries have____ to be a source of global economic development and essential to generations.
His best movie was about the life of Gandhi in India, ______ won several Oscar awards.
—Did you hear about the hero who rescued the child from the burning building?—Yes. What do you think most people ______ if they were in a similar situation?
A person , when_________,can often do what is normally beyond his ability.
Mark needs to learn Chinese ______ his company is opening a branch in Beijing.