（15）28. – There are three ( ) assistants in that ( ) shop.
A. women ; shoe B. woman ; shoe C. woman ; shoes D. women; shoes
正解：A 分析：
（16）29. – The computer on the desk is ( )
A. twins B. the twin’s C. the twins D. the twins’
正解：D 分析：
（17）30. – They are going to have a picnic ( ) next week.
A. sometime B. some time C. sometimes D. some times
正解：C 分析：
（18）34. At the foot of the hill you could hear nothing but the ( ) of the running water.
A. shout B. noise C. voice D. sound
正解：D 分析：
（19）35. – Heilongjiang is in the ( ) of China.
A. northeast B. northeastern C. northwest D. northwestern
正解：A 分析：
（20）60. – All the ( ) teachers enjoyed themselves on March 8th , because it was their own holiday.
A. man B. men C. woman D. women
正解：D 分析：
（帮我分析一下吧，谢谢大家拉）
全部啦！
追答（15）28. – There are three ( ) assistants in that ( ) shop.
A. women ; shoe B. woman ; shoe C. woman ; shoes D. women; shoes
正解：A 分析：
名词 + 名词 ：前面名词最定语修饰后面名次时，一般情况是 前面名词只用单数，只变后面名词
如： book cover - 书皮， 许多书皮就是: a lot of book covers,
a shoe shop, two shoe shops..
但当前面名词是以下词语时：
man, woman ，sales, sports, news, overseas, herdsman(牧人）=shepherd,
前后都要变复数。