Fill in the blank (correlative with “Hardly … when”) “Hardly had he arrived ______ it started raining.” Choose the correct connector.

Given data

• Sentence begins with “Hardly had …” indicating an immediate subsequent event.

Concept/Approach
The fixed correlative is “Hardly had X happened when Y happened.”

Option analysis
when — correct pairing.than — pairs with “no sooner … than,” not “hardly …”then/that — ungrammatical here.

Final Answer
when