Se podría creer que se forma el past perfect en frases con un verbo modal de la misma manera en la que se forma el present perfect con un verbo modal pero utilizando el simple past del verbo modal en vez del simple present. Pero no es así. Como ya lo hemos mencionado varias veces, el simple past de un verbo modal sirve para formar el condicional y por lo tanto no se puede utilizarlo para formar el past perfect. Lo que se recibe haciéndolo es un condicional II.
Para evitar cualquier ambigüedad hay que construir con una perífrasis.
ejemplos | ||||
---|---|---|---|---|
verbo auxiliar | perífrasis | perífrasis en el past perfect | ||
can => | to be able to | had been able to | ||
may => | to be allowed to | had been allowed to | ||
must => | to have to | had had to | ||
to be obliged to | had been obliged to | |||
to be forced to | had been forced to | |||
to be compelled to | had been compelled to | |||
shall => | to be to | had been to | ||
will => | to want to | had wanted to | ||
to wish | had wished to |
Para ver más claro.
Present perfect: I have seen him.
con un verbo modal: I can have seen him
Past perfect: I had seen him.
con un verbo modal: I could have seen him.
=>Es un condicional: Habría podido verlo.
Past perfect: I had seen him.
I had been able to see him.
=> Había podido verlo.