21.   Booms are rubber-like materials that float like a curtain and extend about a foot below the surface to contain spills.

22.   A building boom was forecast.

23.   A construction boom is under way, with new homes, bridges and streets.

24.   A boom is under way in the sale of financial advice.

25.   Across this region, which has long felt culturally overshadowed by other parts of the country, an extraordinary building boom is under way.

26.   Business booms are famous for hiding underlying problems in an economy.

27.   But for one group, the soundtrack boom has been a mixed blessing.

28.   But for every energy boom there is a bust.

29.   But perhaps because an export boom was under way, consumers recovered their spirits within a couple of months, and the index bounced back.

30.   But sometimes the booms have been louder.