era el único que

was the only one who

→ ser
phrase Rare #28,634
was the only one who Used to say that one person alone did something, knew something, or had a certain quality. The phrase often introduces a relative clause, as in 'era el único que + verb'.
SP: Tom era el único que sabía prender fuego sin fósforos.
EN: Tom was the only one who knew how to start a fire without matches.

Porque Jackie era el único que podía decir lo contrario.

Because Jackie was the only one who could say otherwise.

— Mike y Nick y Nick y Alice (2026)

Yyo no era el único que tenía toda la atención.

And I wasn't the only one getting all the attention.

— American Splendor (2003)

Tom era el único que respetaba a Mary.

Tom was the only one who respected Mary.

Tom no era el único que sonreía.

Tom wasn't the only one smiling.

Tom era el único que estaba dispuesto a abordar el delicado tema.

Tom was the only one willing to address the delicate subject.

Tom se dio cuenta de que era el único que podía salvarle a Mary.

Tom realized that he was the only one who could save Mary.

Él era el único que no era una máquina.

He was the only one who wasn't a machine.

— 3 Idiots (2009)

Tom era el único que sabía prender fuego sin fósforos.

Tom was the only one who knew how to start a fire without matches.

No era el único que no conocía a Tom.

I wasn't the only one who didn't know Tom.

Tom era el único que confiaba en María.

Tom was the only one who trusted Maria.