What's it called when a brivla requires {be}?

[Pierre Abbat <phma@phma.optus.nu>]

IIRR there are three constructions in the grammar where a brivla requires {be} 
if it has arguments. One is a selgadri, one is a seltau, and I forget what 
the third one is. What do we call the state a brivla is in when it requires 
{be}? I've thought of saying that it's in the infinitive, but the semantic 
equivalent of an infinitive is {lo nu} followed by a brivla. Anyone have a 
better name?

Pierre