Generally, when you marry a U.S. citizen and apply for Lawful Permanent Residence status (green card) after being married for less than two years, you will receive a conditional, two-year green card instead of the ten-year green card. Thus, in two years you will have to file Form I-751 to remove conditions on your two-year green card. U.S. Citizenship and Immigration Services (USCIS) issues a two-year green card in these circumstances to ensure that the marriage was not entered solely for the purpose to evade immigration laws. 

Therefore, when the time comes to remove conditions on your status, you need to file Form I-751. Usually, this petition is filed jointly with your spouse. However, there are circumstances when filing jointly is no longer possible. In such cases you need to request from USCIS that the joint filing be waived or individually filed. To seek this waiver, you will need to establish that one of the following has occurred:

- Your spouse is deceased
- Your marriage was entered in good faith but it is now terminated through divorce or annulment
- Your marriage was entered in good faith but your U.S. citizen spouse battered you or subjected you to extreme cruelty. 
- You will suffer extreme hardship if your status is terminated and you are removed from the United States. 

USCIS may still deny your petition even if you seek a waiver on one of the following grounds mentioned above. Please be advised that there are special considerations in each case and this post does not address all of them. It is best to consult with an experienced immigration attorney.