is one of only two verbs in Japanese that do not follow the standard rules of conjugation for Godan
verbs. The other primary verb being する
means ‘to come’, or ‘to be coming’.
will always have the particle に
attached to the location that someone ‘will come’, or ‘has come’.
The reason that 来（く）る
is called a か-column irregular conjugation verb in Japanese is because the る in 来（く）る
does not conjugate, but is dropped. This leaves the く being the part that conjugates. Because of this, 来る has qualities of both る-Verbs
(the る being dropped), and う-Verbs
(the remaining く changing depending on the conjugation). Here are some examples of how 来（く）る
（き）た, （く）る, （こ）ない
will often be seen as 来（き）ている
when someone has come to a place and remains there. This is due to ている
meaning ‘to exist in the state of an action’, rather than being exactly the same as ‘(A)~ing’ in English. Because of this, 来（き）ている
can mean either ‘to be somewhere that one has come’, or ‘to be coming’.
Sometimes the difference between these two will not be clear unless there is further context.
来（き）ている (for existing at a place) is only used for places that people ‘temporarily’ go, so will not be used when you are at your home/work.