For reopening questions do the following
1.flag the question
2.choose moderator attention and other optional buttons on the popup window
3.state the reason why it need to be reopened in others box
As the users usually post their request to reopen their questions and it lead to increase in spam if they goon requesting their questions ..
follow the simple procedure to bring moderator attention to reopen the question,the moderators will consider and reply it as soon as possible