Task: Question Generation
Input (English): Passage: In 1905, 1,003 Korean immigrants, which included 802 men and 231 women and children, departed from the port of Chemulpo, Incheon aboard the ship Ilford to Salina Cruz, Oaxaca, Mexico. The journey took 45 days, after which they took a train to Coatzacoalcos, Veracruz. In the Veracruz port, another boat was taken to the port of Progreso with the final destination being the capital city of Mérida, Yucatan. They arrived in May 1905, with previously signed contracts for four years' work as indentured laborers on the Yucatán henequen haciendas. Many of these Koreans were distributed throughout the Yucatán in 32 henequen haciendas. The town of Motul, Yucatan, located in the heart of the henequen zone, was a destination for many of the Korean immigrants. Subsequently, in 1909, at the end of their contracts, they began a new stage in which they scattered even further  Thus, the majority of those who came were single men who made or remade their family lives with Yucatecan especially Maya women. While Korean girls were much more subject to marriages arranged by Korean parents, males had greater freedom when it came to making a family. This rapid intermarriage by Koreans, coupled with geographic dispersal, prevented the establishment of close social networks among these migrants and therefore provided the basis for Korean descendants among the Yucatan Peninsula. After that 1905 ship, no further entries of Koreans into Mexico were recorded, until many years later, leading to a new community of Koreans with completely different characteristics from those who entered in 1905. These descendants have started the Museo Conmemorativo de la Inmigración Coreana a Yucatán, a museum for the remembrance of their ancestors journey.
Output (English): How many years did the immigrants have to work as indentured laborers?