Facebook began testing the software in the United States in March.

Facebook 于 3 月开始在美国测试该软件。

At the same time, Boeing is testing new flight control software for the MAX, hoping to get approval to fly the plane again later this year or early 2021.

与此同时，波音公司正在测试MAX机型的新飞控软件，希望今年年底或明年年初该机型的复飞能审批通过。