Sun Tao has had a English course, but he still doesn't know
A. six-month; how to spell this word
B. six months; how spell the word
C. six-months; how he should spell this word
D. six-month; how should he spell the word
网友回答
(答案→)A. six-month; how to spell this word
B. six months; how spell the word
C. six-months; how he should spell this word
D. six-month; how should he spell the word
解析：six—month“六个月”，是由“数词+名词”构成的复合词，其中的名词不可用复数形式；后一空为“疑问词+动词不定式”作宾语。