"Gedung ini sudah digunakan ketika perguruan tinggi ini didirikan."

Translation: This building was already being used when this university was founded.

[donny309620]

"This building was already in use at the time this university was established" should also be acceptable.

[8enP1jip]

Should be "... When this university was founded"

[Sam67858]

Yes. Can’t mix tenses in one sentence!

[Fosdick1]

Why is my answer "This building was being used already when this university was founded" incorrect?

[BenShaw495]

"This building was already being used when this university was founded" should be accepted.