Choose the correct sentence

“when” conjunction has an important function to compare two short - and long - term actions in English. But the tip here is that short - term action is used in Simple Past Tense and the “when” conjunction is placed before the action to emphasize this action. The comma in “while” is also a valid property for the “when” conjunction.

Example:

• When the doorbell rang, I was sleeping.
• John was playing the guitar when Linda came in.

Formulation:

• (When) + (Simple Past Tense) (,) - - > (Past Continuous Tense)
• (Past Continuous Tense) (When) - - > (Simple Past Tense)

SO,'When we saw her last, she was running to catch a bus.' - Is correct