[NP^ Alice]
[NP [N Alice] and [N Bob]]
[S[NP[N Alice]][VP[V is][NP[N'[N a student][PP^ of physics]]]]]
[CP [NP^_1 What] [C' [C_b did] [IP_2 [NP^ you] [I' [I tr<b>] [VP [V' [V eat] tr<1>]]]]]]
Movement 2 Movement 3