A．Take precautions to reduce the risk of sudden infant death syndrome．
B．Sleep in the same house but not in the same room as their babies．
C．Sleep in the same room but not in the same bed as their babies．
D．Change their sleep patterns to adapt to their newborn babies’．
A．More money is needed to record the native languages in the US．
B．The efforts to preserve Indian languages have proved fruitless．
C．The US ranks first in the number of endangered languages．
D．A lot of native languages have already died out in the US．
A．To set up more language schools．
B．To educate native American children．
C．To revitalise America’s native languages．
D．To document endangered languages．