Trains and Railway Stations - Trains and Railway stations are obvious symbols of change, with all of the comings and goings that occur on or at them.  In this novel they are special symbols of change because of all of the additional important things that occur on or at them that cause things to change.  Anna and Vronsky first meet at a railway station; Anna first becomes dissatisfied with Karenin at a railway station (his large ears); Vronsky declares his love for Anna at a railway station; Anna kills herself by jumping under a train; Vronsky's intention to go to war is revealed on a train.

English novel - A few times in the novel we see Anna trying to read an English novel.  This symbolizes Anna's trying to escape her situation through reading about others.  We can also see her trying not to 'see' her situation when she screws up her eyes numerous times at the end of the novel.  She even admits that she has tried not to think about it.

Frou-Frou - The mistake that Vronsky makes with this mare during the race and the horse's death foreshadow Anna's ultimate death.  In both cases Vronsky loses control over the situation and there are deadly results.

Peasant Couple - For Levin the peasant way of life, and especially the peasant couple he observes and envies, symbolizes pure and simple life.  For a while he believes that all of his problems would end and that he could find true love if he were to renounce his position and marry a peasant woman.  He soon realizes the folly in this idea, but he does find comfort in working with the peasants and in the manual labor.