Lovely language, very expressive, can be very simple (as sometimes when spoken by inland tribes, who might come to Swahili later in life) or highly complex, as when spoken by the people of Zanzibar or the Coastal regions of the East coast of Africa - mombassa, Dar and so on.

Verb formation, in a nutshell:

I: ni-
you: u-
he/she/it: a-
we: tu-
you (pl): m-
they: wa-

Present tense: -na-
future: -ta-
past: -li-
past perfect: -me-

root: ku-

Find the root for a verb, then mix and match the above.

Example: kuenda, to go (enda is the root)

tutaenda - we will go
wameenda - they have gone
ninaenda - I go

Some other verbs to play with: kutembeya - to walk, kuona - to see, kucheza - to play. Have fun!

Thanks, Gritchka for the corrections - Nashikuru kwa mafundisho mzuri. Samahani kwa kiswahili kibaya :)