`y`_{1}, ..., y_{n} occur free in M, this:
+If we answer Q2 by permitting reduction inside abstracts, and we also permit eta-reduction, then where none of `y`_{1}, ..., y_{n}

occur free in M, this:
`\x y`_{1}... y_{n}. M y_{1}... y_{n}

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2.11.0