I speak spanish pretty well! (Hablo español bastante bien)
In railway signalling, an interlocking is an arrangement of signal apparatus that prevents conflicting movements through an arrangement of tracks such as junctions or crossings. The signalling appliances and tracks are sometimes collectively referred to as an interlocking plant. An interlocking is designed so that it is impossible to display a signal to proceed unless the route to be used is proven safe.
Answer:
Yo lleve mis papeles a la clase
Gustavo y yo terminamos nuestra traeas
Tu comprastes tu calculadora en la libreria
Ustedes halban con su abulea?
Ana estudia para su examenes
I hope this helps. I'm not sure if you needed a double check but I corrected some improper grammar.
Correct, they would be Ella,El, etc. but common ones are: Ellos, singular, and ustedes.