the difference between then and than

[wrongnumber]

Hardly had we arrived than the problems started. (source: https://www.oxfordlearnersdictionaries.com/definition/english/than?q=than)
Can than be subtituted with then in the sentence ?
Does than overlap the meaning of next actions on a timeline with then or just in expressions?

 

[emsr2d2]

No, you can't use "then" there. It's a fixed expression.

Hardly (past perfect separated by person) than (noun/person + past simple).

Note these different ways of saying the same thing without using that construction:
We had only just arrived when the problems started.
We arrived, then immediately the problems started.

 

[teechar]

Can than be substituted with then in the sentence?

No. Those are completely different words in English.

Take a look at the structure in the following link:

Hardly, no sooner (examples, how to use)

We can use hardly or no sooner to say that two things happened in quick succession (i.e. there was a very short space of time between the two things happening). No sooner We use no sooner in a simi…

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