Please explain what I do?

[williamgeff]

Google says don’t use different keyword in on-page title and keywords, don’t used (in, off, for) title.

Cheap Widget Company in Kolkata (Not ok)
Cheap Widget Company Kolkata (Ok)

[edited by: goodroi at 2:56 pm (utc) on Sep 6, 2016]
[edit reason] Please no specific keywords, widgetized [/edit]

[htmlbasictutor]

Those are what are called stop words.

Here is an article by SEO by the Sea that explains. It's old but you can still read it.
New Google Approach to Indexing and Stopwords
seobythesea.com/2008/01/new-google-approach-to-indexing-and-stopwords/
(not affiliated with site, just follow it)

[keyplyr]

Hi williamgegg Welcome to WebmasterWorld [webmasterworld.com]

It may be advised not to use prepositions & other non-entities since they do not count as search term matches, however Google also says build your web site with the visitor in mind and don't optimize for search engines.

If it doesn't look good for the visitor, the results will be worse.

[NickMNS]

I don't know where read or heard that "Google says" :

don’t use different keyword in on-page title and keywords, don’t used (in, off, for) title.

The concept of stop words comes from NLP (natural language processing). It is true that for certain NLP tasks stop were are removed. But when it comes to interpretation of language for the purpose of determining user intent stop words are essential.

Example:
With some stop words:
Buy Cheap Widget Company in Kolkata
Buy Cheap Widget for Company in Kolkata
Buy Cheap Widget at Company in Kolkata

Without: Cheap Widget Company Kolkata

So what is your site about?

The Google mantra is, and just good common sense:
Your site needs to be created for real human users, not designed for robots.

[martinibuster]

I agree with Nick. The challenge with keywords is communicating how the page satisfies a users intent. The OLD way with keywords was to match keywords with search queries. That's optimization for a search engine that no longer exists.

[wittycookie]

You can make title with "in" or without "in". Google shows same results with both. Google automatically detect these thinks.