The second stage involves testing the features of the software to ensure they are performing as intended.

第二阶段是测试软件的功能，以确保它们按照预期的效果运行。

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The new drug, which is now in second-stage testing on hundreds of patients, blocks only the receptors involved in fear and anxiety.

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The Astana star won the testing stage in 31 minutes 59 seconds with Team Katusha's Toni Colom in second place, 22 seconds adrift.

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In December 2010, when two cracks were discovered at the end on the second-stage engine nozzle on the Falcon 9, a cadre of NASA experts urged extensive analysis and testing before attempting to launch.

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