Key Difference: Then is generally used to denote next or the time in question. Than is generally used to introduce the second term in a comparative statement.

Two words that often create confusion are then and than. They look and sound similar and therefore, many times we use them interchangeably. The use of one in place of another can turn out to be a blunder. Thus, it is important to determine the differences between these two terms.

Oxford dictionary defines then as

1. At that time; at the time in question:

2. After that; next; afterwards:

3. In that case; therefore:

It can be used as an adverb, an adjective, a noun or an idiom. Let us take some examples in order to understand then.

1. In 1973, he was awarded by the then President.
2. He first went to watch a movie, and then went for a walk with friends.
3. If she recovers in few weeks, then there would be nothing to worry about.

It is also used in a phrase stating ‘there and then’ meaning immediately. For example, ‘she got the visa and she booked her tickets there and then’.

Oxford dictionary defines than as

1. introducing the second element in a comparison:
2. used in expressions introducing an exception or a contrast:
3. used in expressions indicating one thing happening immediately after the another

 Some examples for than are listed below:-

1. Cheese pizza is better than a simple pizza.
2. He might take away everything other than his paintings.
3. I like swimming more than cycling.

The simple rule to apply is that generally for comparisons we use than and for time related context we use then.

Her singing is better than her dancing. In this example, the comparison between singing and dancing is made. Therefore, than is used to introduce dancing in the comparison, as the second term. She sang and then danced. In this example, dancing is preceded by singing and therefore, it is describing an order in which two activities/events took place. Therefore, then is suitable to be used in this sentence. It is primarily used as a conjunction or a preposition.

Thus, we can say that both are quite different from each other and thus, should be used with proper care and attention. The difference may be simple than the expected difference, but still you need to remember the definitions of each. If definitions of both are clear, then there is nothing to worry about.

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