as if / as though = come si
He looked as if he would burst out in tears any minute.
Tenía pinta como si en cualquier momento se ponía a llorar.
We were pretending to be happy, just as if nothing had happened.
Fingimos de estar felices, como si no hubiera ocurrido nada.
The man drove on as though he didn't see the accident.
El hombre se fue como si no hubiera visto el accidente.