Continuity mistake: When Rick and the Emperor are fighting in the end, while they are punching and kicking each other, the Emperor suddenly turns around and is hitting Rick with the back of his elbow after one cut, but if you watch closely, you can tell he didn't have time to turn around, nor did he even start to turn- he simply has turned 180 degrees between shots.
Continuity mistake: In the very last fight, when Rick jumps down and charges the Emperor, watch his hands. In the first shot, they're moving back and forth as he runs. Then it cuts, and they're instantly up like a boxer despite him having no time to lift them between edits. Then it cuts to a shot from behind, and you can tell from his shoulders that he no longer has his arms up. Again, there's not enough time for him to have lowered his arms between edits. It goes by quickly so you have to pay close attention.
Continuity mistake: During the big chase, when Alex is under the chariot, he lets go, spins around and climbs up the back with Lin's help. In one shot under the chariot, you can see that he has a big hole in the left kneecap of his pants. But a few shots later as he's climbing up the back, the hole disappears and is missing throughout the rest of the scene. Seems the wardrobe got damaged and then replaced during filming.
Continuity mistake: When Evie goes to seduce Rick, she pulls the belt on her gown and the camera cuts. Instantly between cuts, her robe is suddenly open.
Audio problem: When Jonathan leaves at the very end of the film, watch the valet's face. When he says the lines "Let me get your bags, sir" and "Where you off to, Mr. Carnahan?", it's very clear he's not actually saying the lines. In fact, his chin/mouth are barely moving at all. Jonathan's dialogue "Don't touch it, don't touch it!" also seems to not match. It seems like every single line in the scene before "Step on it, I've got a plane to catch!" was either (poorly) dubbed or added during post-production.
Continuity mistake: When Rick tells Alex that he put down "more mummies" than him and Alex replies "You put down ONE mummy, dad!" watch Alex's head. In the first shot, he's facing Rick. When it cuts, suddenly he's instantly looking to his right, and then he turns his head to face Rick again.
Revealing mistake: When Lin flies down and kicks the evil general into the gears, it's painfully obvious that the actress is on a wire. Her body unnaturally sort of floats as she's performing the kick, then after she's made contact with him, you see her unnaturally move backwards and land on the ground while clutching something invisible (presumably the wire that was painted out) in her hand. When she lands on the ground, it's also clear from her feet not touching the ground "properly" that she's being suspended.
Audio problem: When the Yeti kicks a "goal" with the soldier and the gate, pay attention to the shots and the soldier's scream. In the second shot, the soldier is an instant away from hitting the gate - he's literally only a few feet away from it. Then it cuts to a shot of the Yeti watching, and you hear the soldier continuing to yell for several seconds, even though you should hear him hit the gate. It then cuts back to the soldier and he finally hits the gate. The timing of the scream makes no sense.
Continuity mistake: When Alex arrives at the club towards the beginning, Jonathan pulls him away from the pretty woman and gets him a drink. The camera is behind them in a medium-wide shot, then cuts to a side shot as the pretty woman walks by and Alex watches her. Except when the camera cuts, the pretty woman just sort of appears right next to Alex, when she wasn't visible in the previous shot. Jonathan also goes from looking straight forward at Alex to looking to his right at the bar between the same cut.
Audio problem: When the O'Connells and Lin meet at the club and Lin is explaining what needs to happen next, at one point she says the line "beyond it is a golden tower." If you look closely, the words she's saying and her mouth movements don't quite match. (Only the word "tower" matches... nothing else.) It's an over-the-shoulder shot of her, and her mouth is a little out-of-focus, but you can tell. The line was very likely redubbed in post-production, and thus wasn't said at exactly the same speed.
Continuity mistake: During the short scene when Jonathan is talking to the yak at the camp, he instantly goes from facing sideways at the yak to facing forward at the campfire between edits at one point.
Continuity mistake: When Rick, Alex and Jonathan are going over their plan at the mountain temple, watch Jonathan's hands when he sits down. He takes both of his gloves off. However, during one quick shot in the scene (where Jonathan says "Me?"), suddenly his left glove is back on. The next time you see him a second or so later, both gloves are back off again. There's absolutely no reason why he'd put one glove back on only to take it right back off, nor would there be enough time for him to do so between edits.
Continuity mistake: During the final battle, when Mad Dog and Jonathan are in the plane, Mad Dog remarks about his men drinking for free at Jonathan's bar, and it cuts to a closer shot of Jonathan. In the first shot, Jonathan isn't holding the plane's doorway, but in the second shot, he is. Additionally, Jonathan goes from facing forward to facing Mad Dog between the edits, and a gun appears in front of Jonathan in the second shot that wasn't there in the first shot.
Continuity mistake: During the final battle, when the planes arrive, pay attention to Evie when she says the line "Jonathan certainly knows how to make an entrance!" Between cuts, she instantly goes from being about two feet away from Rick to pressed right up against him.
Continuity mistake: During the chase scene, after Jonathan says "We can use this!" Rick rips the top off a large box and throws it behind him. In the first shot, only Rick is lifting the box-top, but when it cuts to the next shot, suddenly Jonathan is helping him lift it. The cut is instant, so there's no time for Jonathan to have reached down and grabbed it between edits.
Continuity mistake: When Alex and Rick are discussing their guns and battle tactics, when Alex says the line "I say we ambush them with long-range rifles...", pay attention to Jonathan sitting in the background. In the first shot Jonathan only just starts to stand up. But then it cuts to a closeup of him, and he's not only standing all the way up, but he's also walking to the left. The cut is instant, so there's no time for him to have finished standing up and started walking between the cuts.
Continuity mistake: During the final fight, around when Rick says "Enough tricks! Where is your honor?!" there's a quick shot of Alex unconscious. His body is leaning against a pillar. About 2 seconds later, Rick runs up on top of a globe-shaped structure (right before he says "Fight like a man!"), and Alex is visible on the side of frame - he's in a completely different position and no longer leaning against the pillar. There's not enough time for him to have moved between the two shots, plus he's knocked out.
Continuity mistake: At one point during the big battle, Rick and Evie run up a small hill and Rick grabs a sword from the ground after running out of ammo. Evie is behind him. The camera cuts to a different angle as Rick charges at some terracotta warriors, and suddenly Evie is in front of him and running behind him again.
Audio problem: When Yang is about to bring the Emperor to life, he says "Once this touches him, the Emperor will rise... to rule again!" When he says "to rule again!" his mouth is closed. It's a very wide shot, so you have to look closely to notice... but his mouth is definitely closed.
Continuity mistake: When she's first given the Eye of Shangri-La by her old associate, Evie is holding it and the box it came from in front of her is open. There's a few very quick cuts, and suddenly she's no longer holding it and the box in front of her is closed. There's no time for her to have put it away and closed the box between cuts, nor do we hear the box being closed. It seems like a few shots of her putting it away has been edited out to quicken the pacing of the scene. Regardless, it's a mistake.
Answer: Reading and speaking many Eastern languages can be entirely different tasks so it's perfectly plausible that she knew how to translate the writing but not how to speak it.