[译] 警察问他是怎么回事。
[误] The policeman asked him what the matter was.

[正] The policeman asked him what was the matter.
[注] 宾语从句中要用陈述语序，而 what is the matter? 中的 what 本身就做主语，因此，在变成间接引语时，语序不用调整。