-- RULES FOR HABEN vs. SEIN -- 1) You usually use "haben" in most cases to build the perfect tense. (Ich habe gegessen) 2) Use "sein" for verbs that indicate a change of location through movement or a status change (Ich bin gelaufen, Ich bin angekommen, ich bin Mutter geworden) 3) Do always use "haben" for all verbs that include accusative objects, even if point 2 is true for them (e.g. "Ich habe die Wohnung verlassen") 4) Exceptions are: "sein" (Ich bin in der Stadt gewesen) and "bleiben" (Ich bin in der Stadt gewesen).