请教几个困扰我多天的语法真题

1。9508 39

The main advertising media include direct mail, radio,television,magazines,and

newspaper

newspaper确实有错，但direct mail没错吗，难道mail是不可数名词？

2。9605 14

Hiram Revels, the first Black member of the United States Senate, served as senator from Mississippi, an office       he was elected in 1870

which   to which    and which    being which

我觉得which没错啊，如：Bob was elected the chairman of the committee

3。9905 34

In the 1930's few major orchestras in the United States hired woman, so many chose to perform in amateur musical groups as an alternative

前面用many，后面怎么用了单数an alternative?

望高手不吝赐教 谢谢

1.mail: letters sent by post offices.

2.Bob was elected the chairman of the committee

Bob was elected to an office

3.an alternative  means "to perform in amateur musical groups"

mail在学术英语中多数做不可数用，如：a piece of mail。当然偶尔也会听到 an email的说法。

elect的宾补用法如下：

be elected chairman of the committee正确

be elected to the committee正确

alternative在这里是选择的意思，与人无关。

2.which指代an office，该定词从句其实可颠倒写为he was elected to which in 1870。

3.so many后面省略了women

弱弱的问一句：

NEWSPAPER怎么错了？不是不可数的吗？