Now it took years to build up the infrastructure for polio eradication -- more than 15 years, much longer than it should have -- but once it was built, the results were striking.
我们花了很多时间来发展基础建设 为的是根除脊髓灰质炎 超过十五年，比我们预计要长 但一旦建成，效果是显著的