these principles allow control verbs to be explained by movement and what had previously been analyzed as pro is instead treated as the trace of dp/np-movement. consider the example in (24): to derive (24a) the dp john moves through several positions, and checks a θ-role at each landing site; this is shown in (24b). in this way, the chain of johns satisfies the agent θ-role of the verb hope, as well as the agent θ-role of the verb leave. in the movement analysis, multiple θ-role assignment does the same work as allowing obligatory control of a pro subject.