2.3. "This is the laptop I´ve just bought"

Actividad
- This is the laptop (which) I´ve just bought → laptop es el objeto
(Este es el portátil que acabo de comprar)
- Sara was the girl (who) I met last summer → girl es el objeto
(Sara fue la chica que conocí el verano pasado)
- He´s the famous singer (whom) I told you about→ singer es el objeto
(Él es el famoso cantante del que te hablé)
Pero aquí no:
That's the boy who is singing tonight (Ese es el chico que va a cantar esta noche) Si quitasemos el pronombre who, nos quedaríamos sin sujeto para el verbo is singing.

Decide si los siguientes pronombres de relativo se pueden omitir o no en las siguientes frases. A continuación, traduce las oraciones al castellano.
1. That´s the smartphone which I´m thinking about buying
2. She was the person who saw it first
3. The e-mail that I sent didn´t reach everybody
4. The flight which we were going to take was cancelled
5. There´s nobody whom I trust more
6. A calendar is something which tells you the date
7. Sam is a person who everybody likes
8. The Guadalquivir is the river which runs through Córdoba
9. Fish is food that seals like eating
10. A computer programmer is a person who designs computer programs