It was as though the dogs were afraid of something.
- C'était comme si les chiens avaient peur de quelque chose.
He went on talking as though nothing had happened.
- Il continua de parler comme si de rien n'était.
He went on reading the book as if nothing had happened.
- Il a poursuivi la lecture de son livre comme si rien ne s'était passé.
He looked as if nothing had happened.
- Il semblait comme si rien n'était arrivé.