I learn SEO recently, and I want to know how can i Distinguish the Competitiveness of the keywords. can anyone help me ?
I am not so clear about what you are saying but I think this link is it: https://adwords.google.com/select/KeywordToolExternal Google's keyword tool can show you how competitive a keyword is. Good Luck.
The Google Adwords external keyword tool can't really be used to determine the competitiveness of a keyword phrase. It can be used to get a feeling for how many times per month people search for the keyword phrase. All you really need to determine the competitiveness of a keyword phrase is Google itself. Search for the keyword phrase in double quotes ("my keyword phrase") to get a feel for the number of pages that have that exact phrase somewhere on the page. Note the number of results. Search for intitle:"my keyword phrase" to find out how many pages have that exact phrase in the <title> element. Note the number of results. Search for inurl:"my keyword phrase" to find out how many pages have that exact phrase in the URL. Note the number of results. Search for intitle:"my keyword phrase" inurl "mykeyword phrase. Record the number of results. These last three searches especially are likely to reveal how many pages are active competing for that search term.
If you are not in the market for a paid tool then googles external keyword tool as mentioned above is perfectly fine
You could also use Good Keywords but that program is kinda trick and didnt really work well for me. http://www.goodkeywords.com/