that (introduces a subordinate noun clause and connects it to its parent clause); Substitutes for another, previously stated conjunction.; when, no sooner; Links two noun phrases in apposition forming a clause without a (finite) verb, such that the complement acts as predicate.
The inanimate direct-object or predicative interrogative pronoun: what; The inanimate subject interrogative pronoun in impersonal constructions.; The inanimate subject interrogative pronoun.