than

Used in comparisons, to introduce the basis of comparison.

• The movie has a different name than I thought.
• The artist worried more than was necessary: there were a lot of people at the exhibition, more than came last year.
• she's taller than I am; she found his advice more witty than helpful; we have less work today than we had yesterday; We had no (other) choice than to return home; I love you more than (what) she does, but less than he, or than I do your sisters.

Because; for.

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.
• No player is more skillful than Greg.

At that time; then.