The main cause of HIV / AIDS infection in China is drug abuse, ______ is very serious in Yunnan.
It was not ______she took off the glasses ________ I realized she was a famous film star.
______ the day went on, the weather got worse.
He went home for lunch____ the clock struck twelve.
The head office of the bank is in Beijing, but it has _______ all over the country.
I’d like to arrive 20 minutes early ________I can have time for a cup of tea.