Movement : aspectual, passive

Verb Movement : Aspectual auxiliaries - have, be
 - aspectual can be positioned inside VP, namely when there is also a modal in the sentence
 - aspectual can be positioned outside Vp, namely when there is a sentence adverb and/or negative element present, but no modal verb
 - in order to account for this situation, we posit movement of aspectual auxiliary verbs from VP to 'I', but only if there is not already a modal verb present in 'I' to block it

NP-Movement : Passive
 - auxiliary verbs subcategorise for VPs
 - the first aux.V is finite, predece the negative marker 'not'
 - modeal aux. -> 'I'

 - if the sentence contains a modal V, then it is positioned in 'I', and any other Vs then being located in VP
 - if there are only non-modal auxiliaries in the sentence, then again the first of these is in 'I', the other verbs being positioned in VP
 - if there is only a main V, then it is inside VP, functioning as the VP-Head