biological
These results suggest that it might be possible to improve academic performance by using chronotherapy to help students retrain their biological clock to become more morning types.（2009)
bitter
However, supertasters also need higher levels of salt to block unpleasant bitter tastes in foods such as cheese.（2011)
blame
Economists blame young people's family dependence on the precarious labor market and increasing housing prices.（2009)
boil
Will water with salt boil at the same temperature as water without salt?（2006)
boost
Genetic engineering got a legal boost in 1980.（2012)
boring
That guy is intelligent but a bit boring.（2007)
bother
In addition to this, many couples now simply live together and don't bother to marry.（2011)
break
Bacteria are tiny creatures. Some bacteria are good. They can help your stomach break down food.（2012)
Break away, break into, break off, break out, break through, break up
breed
Some researchers tried to help. They began to breed whooping cranes in special parks to increase the number of birds.（2013)
