Let's say I want to optimize a page for green widgets but it is not logical to write widgets ( plural ) on my page because i only sell on widget on my page, should i still write widgets or does google rank plural and singular keywords the same way ?
does google rank plural and singular keywords the same way
The quickest way to answer this questions is to go to Google and search for the plural keyword then search for the single keyword and see if there are any changes in the ranks. When you personally observe those rankings you will likely notice some interesting trends among the top ranking sites.
As for the question about singular or plural - I would optimize for whichever keyword will convert the best. Good luck.
You forgot the preliminary check. Does g### know that "widget" and "widgets" are the same word, and that "widgetting" is a completely unrelated word?
If you've had gwt going for a while, look at the "content keywords" list. Some items will seem absolutely correct and proper (rats >> rats, rat, rat's*) while others are useless (new >> new, news, or lives >> lives, lived, live, living, lively -- with "life" as an entirely separate word -- and similarly states >> states, state, stated, stately).
* Yes, OK, I'm quoting. I pulled up a list from a few months ago, before the Paston Letters threw everything out of whack ;) I don't know if it defaults to "rats" because they believe rats normally come in the plural, or because I've got more of that form.
I agree too that it doesn't matter plural or singular but it does matter what is required so go with required and make it master keyword later on its singular or plural automatically comes too with your site.