Enlish is __useful language.We should learn it well.A.a B.an C.the D./
问题描述：
Enlish is __useful language.We should learn it well.A.a B.an C.the D./
答
A
an 加在以元音音素开头的名词前,如an orange
但useful [ˈju:sful]开头字母的发音不是元音音素.所以选A