I was told that in the following construction, only bare infinitive is possible. ? The first thing you should do is wash your hands.
However, I’ve just found the following example. So I wonder which I should trust. ? If you get injured at work, the first thing you should do is to report it to your employer.
Where did you see it? Who wrote it? Are they a native speaker?
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Where did you see it? Who wrote it? Are they a native speaker?
Whoever they are, it's wrong.
Huddleston says that the "to" is optional in those cases.
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