Prepositions of Time in Technical Scheduling and Deadlines
5 exercises — choose the correct time preposition (by, until, for, since, in, at, on) in technical English contexts: deadlines, sprint planning, roadmaps, and incident communication.
0 / 25 completed
1 / 25
The feature freeze is scheduled ___ Friday at 5 PM UTC.
"On" is used with specific days and dates: "on Friday," "on 15 June," "on Monday morning." "At" is used with clock times: "at 5 PM UTC," "at midnight." The correct full phrase combines both: "on Friday at 5 PM UTC." "In" is used with periods and months: "in June," "in Q3," "in the morning" (but not with specific clock times in this context). "By" indicates a deadline (at the latest), not a scheduled point.
2 / 25
All pull requests must be reviewed and merged ___ the end of the sprint.
"By" indicates a deadline: "by the end of the sprint" means "at the latest, at that point." "Until" describes a duration that continues up to a point: "The feature flag will be enabled until the sprint ends" (it stays enabled throughout). "By" is a DEADLINE — a single point in time by which something must be completed. In project management English: "merged by Friday" = Friday is the deadline. "Until Friday" = it continues up to Friday. These are commonly confused by non-native speakers in sprint planning discussions.
3 / 25
We have been working on the migration ___ three weeks now.
"For" is used with a duration (a length of time): "for three weeks," "for six months," "for two hours." "Since" is used with a point in time (the starting moment): "since January," "since the last deployment," "since Monday." "We have been working for three weeks" = duration. "We have been working since Monday" = starting point. "During" indicates within a period ("during the sprint") but is not used with durations expressed in numbers. "In" expresses completion within a period ("we finished in three weeks") — but with present perfect continuous, "for" is required.
4 / 25
The service has been in maintenance mode ___ last Tuesday's outage.
"Since" + a specific past point in time is used with the present perfect to indicate a state that began then and continues now: "has been in maintenance mode since last Tuesday's outage." "For" would require a duration: "for five days." "During" describes something that happened within a period, not the start point of a continuing state. "After" would use simple past: "was put into maintenance mode after the outage." The present perfect + "since" is the grammatical pattern for "it started then and is still the case."
5 / 25
The team expects to finish the refactoring ___ Q3 and launch the new API ___ the end of the year.
"In Q3" = within that period (using "in" for quarters, months, years). "By the end of the year" = that is the deadline for launch. "In" + time period and "by" + deadline point is a common combination in roadmap discussions: "We aim to complete the migration in Q2 and release by summer." "Until" would create wrong meaning: "launch until the end of the year" would imply the launch continues up to that point. "By" correctly signals the deadline.
6 / 25
Slack Message: '@john.doe Just a reminder that the deployment to staging needs to be completed by 10 AM PST tomorrow. Let's aim for a successful rollout before the user group demo.' What preposition best describes the deadline's relationship to the deployment?
'By' is the most appropriate preposition here. It indicates that the deployment *must* be finished no later than 10 AM PST. 'Before' would suggest a time earlier than the deadline; 'during' implies the activity is ongoing at that time and 'after' suggests a time following completion.
7 / 25
PR Description: 'The database schema migration will be rolled out in phases over the next two weeks. Initial testing is expected to occur during the first week and full deployment by the end of the period.' What does 'during' convey about the timing of the testing?
'During' indicates that the testing is taking place *within* the timeframe specified – specifically, the first week. It's crucial to differentiate this from 'before', which would be a time before the period and 'after' indicating a time following it. The word 'immediately' implies an exact point in time.
8 / 25
Standup Update: 'I finished the initial API endpoint design and have started implementing it. I'm aiming to have a working prototype within three days.' What does 'within' denote about the expected completion of the prototype?
'Within' specifies that the prototype must be completed *before* the specified time frame (three days). It sets a limit on when the work is expected to finish. 'Before' and 'at' are also technically correct but 'within' is the most common and clearest phrasing in this context.
9 / 25
API Response: The server returned a message indicating that the service was unavailable since yesterday afternoon. What does 'since' signify regarding the start of the unavailability?
'Since' indicates a point in time *from* which the service became unavailable. It establishes a starting point for the period of downtime. 'Until' would suggest an end date; 'after' implies a subsequent time and 'before' is the opposite.
10 / 25
Slack Message: '@john.doe Just a reminder that the deployment to staging needs to be completed by 10 AM PST tomorrow. Let's aim for a successful rollout before the user group demo.' What preposition best describes the deadline's relationship to the deployment?
'By' is the most appropriate preposition here. It indicates that the deployment *must* be finished no later than 10 AM PST. 'Before' would suggest a time earlier than the deadline; 'during' implies the activity is ongoing at that time and 'after' suggests a time following completion.
11 / 25
PR Description: 'The database schema migration will be rolled out in phases over the next two weeks. Initial testing is expected to occur during the first week and full deployment by the end of the period.' What does 'during' convey about the timing of the testing?
'During' indicates that the testing is taking place *within* the timeframe specified – specifically, the first week. It's crucial to differentiate this from 'before', which would be a time before the period and 'after' indicating a time following it. The word 'immediately' implies an exact point in time.
12 / 25
Standup Update: 'I finished the initial API endpoint design and have started implementing it. I'm aiming to have a working prototype within three days.' What does 'within' denote about the expected completion of the prototype?
'Within' specifies that the prototype must be completed *before* the specified time frame (three days). It sets a limit on when the work is expected to finish. 'Before' and 'at' are also technically correct but 'within' is the most common and clearest phrasing in this context.
13 / 25
API Response: The server returned a message indicating that the service was unavailable since yesterday afternoon. What does 'since' signify regarding the start of the unavailability?
'Since' indicates a point in time *from* which the service became unavailable. It establishes a starting point for the period of downtime. 'Until' would suggest an end date; 'after' implies a subsequent time and 'before' is the opposite.
14 / 25
Slack Message: '@john.doe Just a reminder that the deployment to staging needs to be completed by 10 AM PST tomorrow. Let's aim for a successful rollout before the user group demo.' What preposition best describes the deadline's relationship to the deployment?
'By' is the most appropriate preposition here. It indicates that the deployment *must* be finished no later than 10 AM PST. 'Before' would suggest a time earlier than the deadline; 'during' implies the activity is ongoing at that time and 'after' suggests a time following completion.
15 / 25
PR Description: 'The database schema migration will be rolled out in phases over the next two weeks. Initial testing is expected to occur during the first week and full deployment by the end of the period.' What does 'during' convey about the timing of the testing?
'During' indicates that the testing is taking place *within* the timeframe specified – specifically, the first week. It's crucial to differentiate this from 'before', which would be a time before the period and 'after' indicating a time following it. The word 'immediately' implies an exact point in time.
16 / 25
Standup Update: 'I finished the initial API endpoint design and have started implementing it. I'm aiming to have a working prototype within three days.' What does 'within' denote about the expected completion of the prototype?
'Within' specifies that the prototype must be completed *before* the specified time frame (three days). It sets a limit on when the work is expected to finish. 'Before' and 'at' are also technically correct but 'within' is the most common and clearest phrasing in this context.
17 / 25
API Response: The server returned a message indicating that the service was unavailable since yesterday afternoon. What does 'since' signify regarding the start of the unavailability?
'Since' indicates a point in time *from* which the service became unavailable. It establishes a starting point for the period of downtime. 'Until' would suggest an end date; 'after' implies a subsequent time and 'before' is the opposite.
18 / 25
Code Review Comment: 'The bug fix was implemented last week and deployed to production. We need to monitor its stability closely for the next few days.' Which preposition best describes the duration of observation required?
The phrase 'for the next few days' indicates a period of time following an event. 'During' suggests observing while the event is ongoing, and doesn't fit the context. 'Since' refers to the start date of the fix, not the duration of monitoring, and 'until' implies a definite endpoint that isn't present here.
19 / 25
Standup Update: 'I've been working on the database schema changes for the past two weeks. I expect to have a draft ready by Wednesday.' What does 'for' denote about the timeframe of work completed?
'For' is used to indicate a duration of time over which an activity has been taking place. It specifies the length of time spent working on the schema changes – 'since' refers to a specific point in time and 'until' indicates a deadline.
20 / 25
Sarah: 'The new feature release is scheduled for next Tuesday. We'll be conducting final testing throughout the week and aiming to push it live by Friday afternoon.' Which preposition best describes the timeframe of the testing activities?
'During' indicates that the testing will be happening *while* next Tuesday progresses into the following days. The other options suggest fixed start or end dates, which aren't reflected in Sarah's statement. 'Until Friday afternoon' clearly marks the duration of the testing.
21 / 25
Mark just announced that the performance optimization for the user authentication service will be completed before the sprint retrospective. What does 'before' indicate regarding the timing of the optimization relative to the retrospective?
'Before' signifies that the completion of the optimization is expected to occur *prior* to the scheduled time of the retrospective. It doesn't imply a specific duration or overlap, just an earlier occurrence. The incorrect options focus on durations or overlaps which aren't conveyed by 'before'.
22 / 25
During the daily standup, David stated: 'I'm working on resolving this bug and I expect it to be fixed by Friday.' What does 'by' denote about the desired completion of the bug fix?
'By' indicates a deadline or target completion time. It means that the bug fix should ideally be completed *no later* than Friday; it doesn't preclude finishing earlier if possible. The other options misinterpret 'by' as implying an exact time or a requirement to finish before a specific part of the day.
23 / 25
In a Slack message to the team, Emily wrote: 'The new feature will be released over the next three months.' What does 'over' suggest about the duration of the release process?
'Over' signifies a period of time that includes or spans from one point to another. In this context, it indicates that the release process will take place *throughout* the next three months – it's not a precise timeframe but rather an encompassing duration.
24 / 25
During code review, Alex commented: 'The fix was implemented since last week's outage.' What does 'since' indicate regarding the timing of the implementation relative to the outage?
'Since' indicates causation or consequence. It means that the implementation happened *as a result of* or *following* the outage. The problem was identified and resolved *because* of the disruption, not simply at some arbitrary time. Options 1 and 4 misinterpret 'since' as a temporal relationship without a causal link.
25 / 25
In a project update, Sarah stated: 'The documentation will be finalized within the next two weeks.' What does 'within' denote about the expected timeframe for completing the documentation?
'Within' indicates a limit or boundary of time. It means that the documentation is expected to be finished *sometime* during the period of the next two weeks, but not later than the end of it. This is distinct from 'by' which specifies a precise deadline.
What will I practise in "Prepositions of Time for Technical Deadlines — Grammar Exercises"?
Practise time prepositions in technical English: by vs until for deadlines, for vs since with present perfect, on/at/in for scheduling.
How many exercises are in this module?
This module has 25 multiple-choice exercises, each with instant feedback and a full explanation of the correct answer.
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