工程师在开放前测试桥梁的稳定性。

Engineers ___test the bridge's stability before opening it.

研究人员测试新药物的潜在副作用。

Researchers ___test new medications for potential side effects.

你应该在演示前测试麦克风以确保它正常工作。

You should ___test the microphone before the presentation to ensure it works.