The past continuous tense ('was leaving') is the most appropriate choice to describe an action that was in progress at a specific moment in the past.
The phrase 'just as' signals that two events are happening simultaneously.
The sentence structure implies that the action of the train leaving was ongoing when the speaker arrived at the platform.
Why Other Options Were Wrong
Option A: The simple past tense ('left') is less precise. It suggests the departure was a single, completed event at that moment, rather than a process that was underway.
Option B: The present perfect tense ('has left') is incorrect because it connects a past action to the present. The sentence is set entirely in the past, as indicated by 'reached'.
Option C: The past perfect tense ('had left') signifies an action that was completed before another past action. This contradicts the meaning of 'just as', which implies simultaneity.
Related Visual
Clinical Relevance
Nursing practice connection: This is primarily an exam-oriented knowledge point with limited direct bedside application, so retain English Grammar: Verb Tenses as background academic context rather than a clinical decision trigger.
This is a non-clinical English grammar question and has no direct clinical relevance.
Strong language skills are essential for clear and accurate documentation and communication in a healthcare setting.
What if? - If the stem changed one defining clue so that was leaving no longer matched, reassess the option whose mechanism, classification, or indication now fits the revised presentation.
How to Approach the Question
First, identify the time frame of the sentence. The verb 'reached' is in the simple past, indicating the events occurred in the past.
Analyze the connecting words. 'Just as' is a key phrase that signals two actions happening at the same time.
Consider the nature of the actions. A train's departure is a process, not an instantaneous event.
Evaluate the verb tenses. The past continuous ('was + verb-ing') is used to describe an action in progress at a specific past time.
Select the option that best describes an ongoing action ('leaving') that coincides with a point-in-time action ('reached').
Concept Tested & Keywords
Concept Tested: English Grammar: Verb Tenses
Stem keywords: train, reached, platform
Lead-in keywords: just as
Question ID
Qcb06hjK7FX4SDCNAm1mzg
Practise the full NORCET 10 Prelims-2026
Attempt every question from this paper in a timed mock, then review the full solution for each one.