There are 3 main useage about 过 in mandarin. i will introduce them for you as "use frequence" order. 1. "过" means “have done”so you can use 过 after a verb to express the verb had finished, just like "我看(Vb)过他"，"我吃(Vb)过饭" 2. 过 sometimes means "too much " or "very", it is a adv, jusk like "吃的过多"，“睡得过少”. 3 . 过 in mandarin sometimes use togother with 错 means fault. "过错= fault" , it is a norn , like "这是他的过错" . FInished ， have you catch it ? ^_^ I hope so.

吃过ate 去过visited, passed 过去go(v.), past(n.)

我跟她上过床

1:i can across the river .the across meas "过" 2: you make a mistake .the mistake meas "过" too

过河拆桥~~which means probably someone who have help you before that you should remember and when he has the rouble you may give help, but you forget or tend to forget and do not want to help him