There are 2. Non-past and past. The complicated part is that there are many ways to form them; each having it's own level of politeness and other things.

Hai lula ^^ i know the present — wa — desu. ex: watashi wa rura desu و تنعني : أنا لولا and the past : — wa — deshita. ex: watashi wa lula deshita و تعني : أنا كنتُ لولا و آسف انني لا اجيد كثيرا ،، اتمنى لو لجيبك تماما