Der Infinitiv anstelle eines Relativsatzes steht häufig nach the first, the last, the next, the only.

Beispiele
He is always the last to come to work and the first to go home.
(He is always the last who comes to work and the first, who goes home.)
They were the next to apply for the job.
(They were the next who applied for the job.)
She was the only to wear a costume.
(She was the only, who wore a costume.)

Auch Relativsätze mit einem zusammengesetzten Verb (Verb plus Präposition) können durch einen Infinitiv mit to ersetzt werden.

Beispiele
She has not only three dogs, but also four children to look after.
(She has not only three dogs, but also four children, that she has to look after.)
Bill has a friend to travel with during his vacation.
(Bill has a friend with whom he travels in his vacation.)
There is nothing to be upset about.
(There is nothing that one should be upset about.)