An incident timeline reads: "At 03:14 UTC, the on-call engineer _____ when the first alert fired." Which tense correctly describes an action in progress at the moment of the alert?
Was sleeping is correct. Past continuous (was + -ing) describes an action in progress at a specific moment in the past. "At 03:14 UTC" is the reference point; the sleeping was ongoing. "Slept" (simple past) describes a completed action — it does not convey ongoing background context. "Had slept" (past perfect) implies the sleeping was completed before the alert — that reverses the intended meaning. "Has slept" (present perfect) cannot be used for past time references.
2 / 21
A postmortem states: "The service _____ degraded for 20 minutes before the monitoring system generated an alert." Which tense correctly shows that degradation preceded the alert?
Had been is correct. Past perfect continuous (had been + -ing) describes an action that was ongoing before a reference point in the past (the alert). The degradation started 20 minutes before the alert fired — making the alert the narrative reference point. "Was" is past continuous but does not establish the earlier-than relationship. "Has been" is present perfect continuous — it cannot be used in past narrative.
3 / 21
A root cause analysis reads: "The engineer _____ the wrong configuration file before running the migration script." Which tense sequence is most accurate for establishing that the configuration error preceded the migration?
Had edited is correct. Past perfect (had + past participle) places the configuration change earlier than the migration — establishing the causal sequence. "Edited" (simple past) could be used if the events are listed in strict chronological order, but "had edited" is more precise when the order matters and one event caused the other. "Was editing" describes the action as ongoing at the time of the migration — not the intended meaning. "Has edited" is present perfect — invalid in past narrative.
4 / 21
A changelog entry reads: "Resolved: the service _____ incorrect connection strings after the environment variables were rotated." Which tense best describes the resolved bug behaviour?
Was using is correct. Past continuous is appropriate here because the incorrect usage was an ongoing state that was happening as a consequence of the rotation — it frames the bug as a background condition, not just a one-time event. "Used" (simple past) is also possible but describes the bug as a single completed event, losing the sense of ongoing bad state. "Had used" (past perfect) implies it stopped before another past event — but no other past event is mentioned to create that relationship. "Uses" (present simple) would imply the bug is unfixed.
5 / 21
Which tense sequence is most accurate in this incident summary?
Option C is best. Events in a strict chronological sequence in narrative past can all use simple past: "filled up, crashed, fired." Each event completes before the next. Option A uses past perfect for the first event unnecessarily — past perfect is only needed when the sequence needs explicit clarification (not here). Option B mixes present simple ("fills") with past, breaking tense consistency. Option D creates a contradictory sequence (continuous before perfect) and ends with present tense.
6 / 21
A postmortem timeline says: "At 14:32 UTC, the deploy pipeline _____ when it encountered a network timeout." Which tense correctly frames the failure?
Was running is correct. The pipeline was in progress (past continuous) when it encountered the timeout — the timeout is the interrupting event. Past continuous + simple past is the standard structure for "activity in progress when another event interrupted it." "Ran" (simple past) treats the running as a completed event, losing the sense of interruption. "Had run" (past perfect) implies the pipeline completed before the timeout — reversing causality. "Runs" is present tense, invalid in a past narrative.
7 / 21
An SRE writes: "By the time we received the customer complaint, the error rate _____ to 45%." Which tense correctly shows that the error rate reached 45% before the complaint?
Had climbed is correct. "By the time" introduces a reference point (the complaint), and past perfect establishes that the error rate had already reached 45% before that point. "Climbed" (simple past) would place both events at the same time or in ambiguous sequence. "Was climbing" (past continuous) implies the rate was still rising at the moment of the complaint — which is possible, but "had climbed to 45%" more precisely marks a completed ascent. "Has climbed" is present perfect — invalid here.
8 / 21
A blameless postmortem reads: "The team _____ the new caching layer for three weeks before the race condition was discovered." Which tense best describes the duration of the activity before discovery?
Had been operating is correct. Past perfect continuous (had been + -ing) expresses duration of an action that continued up to a reference point in the past (the discovery). "Had been operating for three weeks" conveys both the ongoing nature and the completed duration. "Was operating" (past continuous) describes the action as in progress but does not convey the three-week duration clearly. "Operated" (simple past) with "for three weeks" is grammatically possible but less precise about the ongoing nature. "Has been operating" is present perfect continuous — invalid in past narrative.
9 / 21
Which sentence uses past tenses INCORRECTLY in an incident report?
Option C is incorrect. "The database had replicated successfully before the primary had failed" uses past perfect in both clauses. Past perfect cannot appear in both the main clause and the before-clause — the temporal subordinator "before" already establishes the sequence. Correct phrasing: "The database had replicated successfully before the primary failed" (using simple past in the before-clause). Options A, B, and D all use past tenses correctly.
10 / 21
A deployment description in a changelog reads: "v3.2.1 _____ at 16:00 UTC. The migration script _____ all user records to the new schema." Which pair of simple past verbs is most appropriate for a factual changelog entry?
Deployed / migrated is correct. Changelog entries use simple past active voice for factual description of what happened. "Deployed" and "migrated" are simple past active: clear, direct, and appropriate for a technical record. "Was deployed / migrated" is passive — acceptable but less direct for a changelog. "Deploys / migrates" is present simple — sometimes used for release notes ("v3.2.1 fixes the login bug") but less natural for describing past deployments. "Had deployed / had migrated" is past perfect — adds unnecessary complexity for a simple sequential log entry.
11 / 21
During a code review of the new authentication service, Sarah noticed an error in the logs: 'User login failed - Invalid credentials.' She immediately investigated and determined that the system was attempting to authenticate users against a staging environment instead of production. Which tense best describes the action taken by the system when the invalid credentials were used?
The correct answer, 'was authenticating,' uses the past continuous tense to describe an action in progress at a specific point in time – when the invalid credentials were used. Options had been authenticating implies a longer duration before the error was detected; authenticated is simple past and doesn't convey ongoing activity; and authenticates is present tense, inappropriate for describing a completed action within the incident.
12 / 21
In a Slack message to the on-call team after an outage, David wrote: 'The service experienced intermittent connectivity issues. By the time we rolled back the deployment, latency had spiked to 500ms.' Which tense correctly describes the secondary event (latency spike) in relation to the initial issue?
'had spiked' uses the past perfect tense to indicate an action completed before another point in the past (the rollback). This accurately reflects that the latency spike occurred *before* the deployment was rolled back. 'spiked' is simple past and doesn't establish a clear sequence of events, while 'is spiking' and 'was spiking' are present tenses unsuitable for reporting a completed incident.
13 / 21
During a code review of the new authentication service, Sarah noticed an error in the logs: 'User login failed - Invalid credentials.' She immediately investigated and determined that the system was attempting to authenticate users against a staging environment instead of production. Which tense best describes the action taken by the system when the invalid credentials were used?
The correct answer, 'was authenticating,' uses the past continuous tense to describe an action in progress at a specific point in time – when the invalid credentials were used. Options had been authenticating implies a longer duration before the error was detected; authenticated is simple past and doesn't convey ongoing activity; and authenticates is present tense, inappropriate for describing a completed action within the incident.
14 / 21
In a Slack message to the on-call team after an outage, David wrote: 'The service experienced intermittent connectivity issues. By the time we rolled back the deployment, latency had spiked to 500ms.' Which tense correctly describes the secondary event (latency spike) in relation to the initial issue?
'had spiked' uses the past perfect tense to indicate an action completed before another point in the past (the rollback). This accurately reflects that the latency spike occurred *before* the deployment was rolled back. 'spiked' is simple past and doesn't establish a clear sequence of events, while 'is spiking' and 'was spiking' are present tenses unsuitable for reporting a completed incident.
15 / 21
During a code review of the new authentication service, Sarah noticed an error in the logs: 'User login failed - Invalid credentials.' She immediately investigated and determined that the system was attempting to authenticate users against a staging environment instead of production. Which tense best describes the action taken by the system when the invalid credentials were used?
The correct answer, 'was authenticating,' uses the past continuous tense to describe an action in progress at a specific point in time – when the invalid credentials were used. Options had been authenticating implies a longer duration before the error was detected; authenticated is simple past and doesn't convey ongoing activity; and authenticates is present tense, inappropriate for describing a completed action within the incident.
16 / 21
In a Slack message to the on-call team after an outage, David wrote: 'The service experienced intermittent connectivity issues. By the time we rolled back the deployment, latency had spiked to 500ms.' Which tense correctly describes the secondary event (latency spike) in relation to the initial issue?
'had spiked' uses the past perfect tense to indicate an action completed before another point in the past (the rollback). This accurately reflects that the latency spike occurred *before* the deployment was rolled back. 'spiked' is simple past and doesn't establish a clear sequence of events, while 'is spiking' and 'was spiking' are present tenses unsuitable for reporting a completed incident.
17 / 21
In a Slack channel, DevOps Engineer Maria wrote: 'We deployed version 2.0 this morning. Immediately after the deployment, the service started experiencing intermittent timeouts – specifically, requests to the /users endpoint were failing with HTTP 504 errors. By the time we rolled back the changes, the error rate had climbed to approximately 15%.'
Which tense sequence is most accurate for describing this incident?
Maria correctly employs the past perfect ('had climbed') to describe a state that existed before another event (rolling back the changes). The use of the simple past describes the initial deployment and the subsequent error. The present perfect ('started experiencing', 'had climbed') is appropriate here because it refers to events that began in the past and have relevance to the present.
18 / 21
A postmortem report states: 'The service experienced significant latency during peak hours. By the time the monitoring team identified the issue, response times had exceeded 3 seconds for 80% of requests.'
Which tense sequence is most appropriate to describe this incident?
The sentence correctly utilizes the past perfect ('had exceeded') to describe a state that was true at a particular point in time before another action occurred (the monitoring team identified the issue). It's important to distinguish between a situation *existing* and an event *happening* - this sequence accurately represents both.
19 / 21
During a standup meeting, Alex reported: 'Yesterday, the API endpoint /users started returning 502 errors. We traced it back to a sudden spike in traffic hitting our rate limit.' Which tense is most appropriate for Alex's report regarding the initial problem?
The simple past ('returned') is best here because it describes a completed action – the endpoint actually returning 502 errors. Using 'was' would imply a continuous state of error which isn't accurate given the report. Option C and D are incorrect because they suggest different tenses are needed to describe the situation; Alex clearly states what *happened*.
20 / 21
In a Slack message to the development team after an incident involving a service outage, Emily wrote: 'The system experienced high latency. We deployed a hotfix and immediately the response times improved.' Which tense is most appropriate for Emily's message?
Emily's message reports on a situation *after* the deployment and its immediate effect. The simple present tense accurately describes a state change or a result that's still relevant. The past perfect would be more appropriate if she were describing the *cause* of the latency before the fix.
21 / 21
A technical lead writes in an incident report: 'We investigated the root cause and determined it was a race condition. After fixing the code, the system returned to normal operation.' Which tense is most appropriate for this statement?
The lead is describing the *completion* of the investigation and the subsequent return to normal operation. Simple past accurately captures this sequence – they investigated, determined the cause (race condition), fixed it, and then the system returned to normal. The other options misrepresent the nature of these actions.
What will I practise in "Past Tenses in Incident Reports — Grammar Exercise"?
Practice simple past, past perfect, and past continuous for accurate incident timelines, root cause analyses, and postmortem narratives.
How many exercises are in this module?
This module has 21 multiple-choice exercises, each with instant feedback and a full explanation of the correct answer.
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