 There is a great deal of controversy over how scope is to be handled. Orthodoxy suggests movement of quantifiers at LF where quantifier scope is made explicit and unambiguous. May (1985) is often cited as the canonical source for this – but it is worth nothing that in that work May treats some LFs as underdetermining some semantic scopal relations. The situation is less clear with temporal and modal (and other) operators: many semantic theories treat tense and temporal adverbs as quantifiers, while some treat modal expression in this manner. Other treat them as the operators or adverbs they appear to be. One respectable semantic tradition sees (P2) as ambiguous, for example, between: