If someone had green card and left US for more than 10 years, do they lose the green card?

Generally a Permanent Resident who has resided outside of the U.S. for 10 years will be deemed to have abandoned his/her residence in the U.S. and his/her Permanent Resident status, and for that reason will need to start the process over again to gain U.S. immigration status. There are exceptions to this, such as for certain missionaries/religious workers, and for others who obtained advanced permission before departing the U.S. (such as for certain employees of the government or of businesses engaged in international trade).