>I have read through the info on this site and other promotion sites and sometimes the info has been conflicting or unclear. Thus I still have some unresolved questions about Meta keywords:
>1. Plurals. I understand that it would be beneficial to include cactus and cacti, but what about words that just have 's' appended to them? Will the search engine automatically find the singular form from the plural? For example, is it better to list both forms of the word (e.g., 'apple, apples'), or just the plural form (e.g., 'apples').
You should use only plurals in your keywords, because a search for "apple" will find "apples", whereas a search for "apples" will only find "apples," not "apple."
>2. Phrases. If a particular word appears in a number of different (legitimate) phrases, would they count that as spamming? For example, 'fishing, fishing tackle, fishing lures, fishing rods'. It seems to me that, in this example, just using the words 'tackle' & 'rods' would not necessarily yield an accurate search because those words could be used for a number of different applications.
Yes, that would be spamming. Every time a word occurs counts as one repetition of that word, regardless of its position or whether it's in a phrase or by itself.
>3. Word stems. Do the search engines count word stems when counting for spam? For example, would the words 'fish, fishing, fisherman' count as three instances of 'fish'?
Yes, that would be three instances of "fish." Try to always use the longest form of a word. "Fishing" will come up in searches for both "fishing" and "fish."
>4. Limits. Are keyword lists limited by number of words or number of characters? What are the limits?
Generally, it's the number of characters. I'm not sure if the limit is the same on all the search engines, but the limit I've always heard is 1024 characters. Of course, the more keywords you use, the more diluted they get, so it's best just to use those keywords that are most related to your site, and try not to use any word more than twice.