Answer:
1. Tú cantas.
2. Ellos conversan.
3. Tú y yo cenamos.
4. La profesora enseña.
5. Mis compañeros viajan.
Explanation:
identifying the person of the narrator, and the time in which it is indicated, we can correctly conjugate the verb, and that it has agreement with what is being expressed.
There could be many answers.
For example:
Tomaron
Robaron
Tocaron
But I think the right answer would be....
Ayer, Roberto y Carlos gastaron 12.000 pesos.