This is the simple form

query human

human [is an instance of] [human being]

human ~[is an instance of] [american footballer]

but if you expect the result set to be large from the first line (as in this case, where there are a lot of humans!) then you can turn pairs of adjacent lines into a join query with the /j modifier

query human

human [is an instance of] [human being] /j

human ~[is an instance of] [american footballer] /j

When a fact is likely to be transient (ie sometimes true and sometimes not, such as someone who was not born an American footballer but became one when he turned 18) then you need to query for a temporal partner.  This query shows the most common form, for when you want to know about facts that are true right now.  You can combine this with the /j modifier in the usual way.

query human

[current time] [applies to] now /1

human [is an instance of] [human being]

f: human ~[is an instance of] [american footballer]

f [applies at timepoint] now

You can also ask for people who we either know aren't American footballers, or we don't know whether they are or not, with the /a modifier

query human

[current time] [applies to] now /1

human [is an instance of] [human being]

f: human ~[is an instance of] [american footballer] /a

f [applies at timepoint] now

Hope this helps,

Beth

Thanks it is reraly helpfull, maybe it is good to post in wiki. That i find there were not so clear, and i leave it having more questions then answers.

Is that the main wiki for the site or particular documentation for the API?  If you mean the main site wiki we're in the process of updating that, but if you mean the API manual then I've not had a look at that so I can pass on your comments if so.

http://www.trueknowledge.com/docs/Query_language

Oh yes, we're aware there's a lot of work needs doing on those.  Someone should get round to it soon.