Are they correct?

Are the followings correct?
1. She has very long working hour.
Amendment: She has to work overtime.
2. She has very long working hours.
Amendment: Her job requires longer working hours.
3. Her working hour is very long.
Amendment: Her working period are very long.
4. Her working hours is very long.
See the amendment in 3.
5. Her working hours are very long.
See the amendment in 3.

You can buy Common Errors in Hong Kong by David Bunton, published by Longman, maybe it can help you.

i think...
1,3

1. 和 4. 錯。

2., 3., 5. 正確。

2014-08-06 19:05:25 補充：
遲了回覆，不好意思：

3. Her working hour is very long.
－－＞　只有一份工作，而工時很長

5. Her working hours are very long.
－－＞　有多於一份工作，而份份工作的工時都很長

2014-08-06 19:07:09 補充：
回 yip******:

Your amendment in 3. should be incorrect.
"Amendment: Her working period are very long."

"period" is singular. It should not be followed by "are".