2. Used in comparisons, to introduce the basis of comparison.
She's taller than I am; she found his advice more witty than helpful; we have less work today than we had yesterday; it's bigger than I thought it was
Preposition
3. Introduces a comparison, and is associated with comparatives, and with words such as more, less, and fewer. Typically, it seeks to measure the force of an adjective or similar description between two predicates.
Patients diagnosed more recently are probably surviving an average of longer than two years.
