Question 29: The size and shape of a nail depends preeminent on the function ………. intended.

intend + for: intend to use, intend to give

Prepositions can be inverted before relative pronouns

In this sentence, “which” replaces the noun “the function”.

Therefore: The size and shape of a nail depends preeminent on the function for which it is intended. = The size and shape of a nail depends preeminent on the function which it is intended for.

The size and shape of the nail depends mainly on the function it is intended to be used for