 
<translate> Hukuncin da ya dace a cikin nassi shi ne: An gudanar da gasar a kowace shekara hudu tun daga 1991, lokacin da aka gudanar da gasar farko, wanda ake kira gasar zakarun mata ta duniya ta FIFA, a kasar Sin. Saboda haka, amsar ita ce 1991. <eng> The relevant sentence in the passage is: The competition has been held every four years since 1991, when the inaugural tournament, then called the FIFA Women's World Championship, was held in China. So, the answer is 1991. 