10 The introductory verbal form וַיְהִי (vayéhi), traditionally rendered “and it came to pass,” serves as a temporal indicator and has not been translated here.
11 Heb “opened the window in the ark which he had made.” The perfect tense (“had made”) refers to action preceding the opening of the window, and is therefore rendered as a past perfect. Since in English “had made” could refer to either the ark or the window, the order of the phrases was reversed in the translation to clarify that the window is the referent.

In other versions

At the end of forty days Noah opened the window of the ark that he had made

After forty days Noah opened a window he had made in the ark

After forty days Noah opened the window of the ark that he had made,

After another forty days, Noah opened the window he had made in the boat

And it happened that at the end of forty days Noah opened the window of the ark that he had made.

And it came to pass at the end of forty days, that Noah opened the window of the ark which he had made:

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