Singular And Plural Keyword Help

[Kirtan]

Hello All,
I have a question. Here it is..
I am optimizing a site. It get #1 and #4 rank in google for, say, Book and Books keyword. But in Yahoo for Book it is at #80 rank and for Books it is at #18. I don't understand this huge ranking difference with singular and plural keyword. Can any one explain it please? Now the question is, which anchor text i have to use when i build links further?

[hhheng]

It doesn't make too much difference. But it's better to use book, because if you search books, page with book can still be showed up.

However, this is just my own experience, you'd better ask somebody else's suggestions.

[cabdirazzaq]

It does actually make a difference whether you use a plural or a singular (depending on keyword). For instance, more people type write "learn study techniques" than "learn study technique" etc, unfortunately Overture keyword selector only gives you singular. You can try out DP;s keyword suggestion tool as they use both Overture and Wordtracker (shows plural as well) : digitalpoint.com/tools/suggestion/