11.   At this time of year, it is common for weather disturbances moving east from the Africa carry dust from the Sahara toward the Caribbean and the Americas.

12.   Because organic polymers break down in sunlight, Wheeler said, the alkoxysilanes are more common for outdoor use.

13.   Because of the energy efficiency of thermal doors, it has become common for houses built in the past few years not to have storm doors.

14.   Bleeding or bloodletting was common for centuries, if not millennia.

15.   A marlin, common for Mexico, was caught off Washington state for the first time in history.

16.   According to Sherman, it is common for women in executive positions to fall back on their staff for occasional child care support.

17.   According to the analysis, the sort of give-and-take Riith enjoyed was far more common for industry representatives than for others.

18.   Burnt offerings appear to be common for the holidays.

19.   But it is common for young woman in her hometown to receive placements through educational exchange programs and agencies that specialize in matching au pairs with families.

20.   But intermarriage is far less common for blacks.