[译] 玛丽很聪明。实际上，她的老师对我说她今年能考上大学。
[误] Mary is very bright. As a fact, her teacher told me that she’s certain to get a university place this year.

[正] Mary is very bright. As a matter of fact, her teacher told me that she’s certain to get a university place this year.
[注] as a matter of fact 是固定搭配，意为“事实上”，用来加强前面所说的话（使前面的话更为肯定，或提供详细情况）。