Chapter 6 aims at accounting for modification by temporal adverbials. The binary approach allows them to operate on different levels of tense structure above S_0. Crucial is the new insight that the relation between modifier A and modified B is not to be expressed as location of A in B but rather as the intersection of A and B. This insight and the flexibility of (deictic) adverbial modification offers the possibility of presenting a structural solution to the Present Perfect puzzle. It also sheds light on the nature of the in/for-test: it explains why terminative sentences with a for-adverbial introduced at a higher level may be regarded as well-formed as opposed to those which require a token interpretation.