Question

was o were
my father at work yesterday

Answer 1

Respuesta:

My father was at work yesterday

Answer 2

My father was at work yesterday

Explicacion:

Como my father es él, es tercera persona por tanto es was. Recuerda que en el pasado se usa was para 1a y 3a persona del singular y were en 2a del singular y 1a, 2a y 3a del plural