What is the meaning of a 90-day stay in Algeria that is valid for two appearances in half a year?

"Algeria is valid for two stays of 90 days for two appearances in half a year" means that within the validity period of the visa, holders of this visa can enter Algeria twice within half a year, and each stay does not exceed 90 days. . According to relevant public information, holders of this visa can stay in Algeria for no more than 180 days within the validity period of the visa, but each stay cannot exceed 90 days, and must be used in two entries within the validity period of the visa. If you exceed the period of stay, you will be deemed to be illegally staying, and you may be subject to fines, entry restrictions and other penalties.