Continuity mistake: The watch on the left hand of the cop holding the binoculars while watching the Eiffel Tower, appears and disappears between shots.
Continuity mistake: When Ursa descends through the White House window, she is facing the back of the cop holding a gun. In the next shot she lands facing somewhere else, the cop now being by her side.
Continuity mistake: When Ursa grabs the snake, in the close-up her badge appears skewed. In the rest of the shots the badge appears straight.
Audio problem: Trapped under the elevator, Lois says "Capital P" but she is not mouthing the word.
Revealing mistake: When Zod takes the rifle out of the cop's hand the strings moving the rifle are seen, each by the side of the cop's cowboy hat when the rifle turns red.
Continuity mistake: The coat hanger in Perry's office disappears between shots.
Continuity mistake: Non smashes Perry's glass but a second later the glass is back in place.
Continuity mistake: After Non smashes Superman against a metal structure which gets totally crumpled, Superman stands up and the structure is undamaged.
Continuity mistake: In the Fortress of Solitude, when Non is (green screened) flying towards Superman, Ursa and Lois disappear.
Continuity mistake: When Superman lands by the truck there are no people behind him. In the next shot there are a lot of people running around behind him.
Revealing mistake: When Ursa blows the helicopter away, the string holding it is visible.
Continuity mistake: In the first scene, when the guard gets caught off-guard by Non his right arm is on the side, in the close up it is bent to defend against Non. A frame later it's down.
Continuity mistake: After crushing Zod's hand, Superman sends him flying away. Luthor's head turns around twice.
Revealing mistake: When Non falls on Superman and breaks the concrete, the hole opens before Non falls on him.
Continuity mistake: When the ring falls on the villains, Non is looking down and a split second later he is looking up.
Revealing mistake: In the ice cave, when Superman makes himself invisible, watch Zod's head jumping slightly to the back, revealing where the scene was edited to achieve the effect.
Continuity mistake: When Non is about to break Perry's desk in half, Jimmy and Lois are standing very close to each other. A split second later they're farther apart.
Continuity mistake: When Lois prepares orange juice, Clark lowers his left arm and sneaks it behind his back. A second later the arm is up.
Continuity mistake: Zod makes a short jump from the white car to the Marlboro truck, but in the next shot we see the two cars are several feet further apart.
Continuity mistake: In East Houston, the army jeep is passing by a brown car, then Ursa talks and we hear the jeep engine coming close, but when the image focuses back on the jeep it is several feet behind the brown car, instead of being in front of it.
Answer: Superman was be able to kiss Lois in such a way that the heightened emotion wiped out her memory of his identity. To answer your second question, even though Lois promised not to tell anyone, Superman decided he does not want even her to know his secret identity.
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