twice a year, whether it is a car ,a bus or a truck, is the rule that every driver must obey in this city.
So _____ that modern industry cannot develop without it.
Scarcely _____ raining _____ the PLA fighters started on their way again.
Never _____ forget the days when _____ together with you.
Mary likes to wear beautiful _____.
It _____ to the airport.