I have = eu am [pres simple]
I had = eu am avut [past simple]
has este pentru pers a III - a singular
ex : he / she /it has [pres simple]
dar la trecut este : he / she / it had [past simple]
I go in Paris = Eu merg la Paris (usual , este o actiune care se repeta) [pres simple]
I am going in London = Eu merg in Londra (in acest moment) [pres continous]
I went in London = am fost in Londra [past simple]