Learn French: Ils ne consomment que pour accumuler. - They only consume to accumulate.

This sentence uses the restrictive structure ne... que, which translates to "only". When you use que to restrict the meaning, it replaces pas. If you wrote Ils ne consomment pas, it would mean "They do not consume."

Why is que placed exactly where it is?

With ne... que, the que always goes immediately before the specific part of the sentence being restricted. Here, it restricts the reason they consume ("only to accumulate"), so que goes right before pour accumuler.

Could I use seulement instead of ne... que to say "only"?

Yes! You could say Ils consomment seulement pour accumuler and the meaning remains exactly the same. The ne... que structure is very common and slightly more elegant, but seulement is a great alternative.

Why do we need pour before accumuler?

In French, to say you are doing something "in order to" achieve a goal, you use the preposition pour followed by an infinitive verb (the unconjugated form). So, pour accumuler translates directly to "in order to accumulate."