You had better ________________ when you have visitors.

A．Those between 18 and 26.
B．Those between 27 and 35 years old.
C．Those between 36 and 45 years old.
D．Women in the l8 to 26 year-old age group.

A．He enjoys writing home every week.
B．He never fails to write a weekly letter home.
C．He doesn’t write home once a week now.
D．He has been asked to write home every week.