Nowadays, my country is undergoing a very difficult financial and social situation.

undergoing 是动词 undergo 的现在分词形式。undergo 由前缀 under-（表示"在...之下"）和 go（"进行、经历"）组成，字面意思是"在...之下进行"，引申为"经历、经受"某种过程或状况。