5 exercises — choose between by, until, within, in, and on for deadlines, SLAs, release windows, and recurring schedules.
0 / 8 completed
1 / 8
A ticket sets a firm deadline for a single point in time. Which sentence is correct? "Please merge the PR _____ Friday at the latest."
"By" for a deadline (no later than a point in time):By Friday means the action must be completed at or before that point — exactly what a deadline expresses. Until Friday would mean the action continues up to Friday, which is wrong for a one-off merge. Within Friday is not idiomatic for a single day. On Friday simply states the day without the "no later than" sense a deadline needs.
2 / 8
You want to say a feature freeze continues up to a release date. Which preposition is correct? "No new commits to the release branch are allowed _____ the release goes live."
"Until" for a continuous state up to a point:Until describes an action or state that continues right up to a moment and then stops — here the freeze lasts until release. By marks a deadline, not a duration, so by the release goes live is ungrammatical (it would need a noun, and the meaning would change). In and within express a period of time, not the "up to this point" relationship the sentence requires.
3 / 8
An SLA promises a maximum response window. Which sentence is correct? "The on-call engineer must acknowledge the incident _____ 15 minutes."
"Within" for a maximum duration:Within 15 minutes means at some point inside that window — the standard phrasing for SLA response times. By 15 minutes is not idiomatic because by takes a clock time or date (by 15:00), not a duration. Until 15 minutes wrongly implies continuing for that period. On is used with days and dates, not durations.
4 / 8
A roadmap describes a future timeframe. Which sentence is correct? "We plan to ship the v2 API _____ the next quarter."
"In" for longer periods (months, quarters, years): Use in with extended periods such as quarters, months, seasons, and years: in the next quarter, in March, in 2026. On is reserved for days and dates (on Monday, on 3 March). At is for precise clock times and certain fixed expressions (at 09:00, at midnight). By would change the meaning to a deadline rather than a timeframe in which the work happens.
5 / 8
A standup schedule fixes a recurring meeting on a specific day. Which sentence is correct? "The sprint retrospective takes place _____ the last Friday of every sprint."
"On" for specific days and dates: Use on with named days and calendar dates: on the last Friday, on 30 June, on Tuesdays. In is for longer periods (months, years). At is for clock times (at 16:00). Within expresses a duration window, not a fixed day. A reliable rule of thumb: at a time, on a day, in a longer period.
6 / 8
Code Review Comment: 'I'm expecting this fix to be deployed by tomorrow morning. Let me know if anything changes.' Which preposition best completes the sentence?
The phrase 'by' indicates a deadline or expected completion time. 'Until' suggests a continuation of a state up to that point, which isn't the intended meaning here. 'In' and 'at' are less precise for scheduling deadlines. Using 'by' clearly communicates the desired timeframe.
7 / 8
Code Review Comment: 'I'm expecting this fix to be deployed by tomorrow morning. Let me know if anything changes.' Which preposition best completes the sentence?
The phrase 'by' indicates a deadline or expected completion time. 'Until' suggests a continuation of a state up to that point, which isn't the intended meaning here. 'In' and 'at' are less precise for scheduling deadlines. Using 'by' clearly communicates the desired timeframe.
8 / 8
Code Review Comment: 'The UI update needs to be finalized and submitted for QA review by the end of next week.' Which preposition is best used?
'By' indicates a deadline – the point in time before which something must be completed. It's commonly used for deadlines relating to deliverables and milestones. 'In,' 'at,' and 'with' don't convey the concept of a defined completion date; they are inappropriate for this context.
What will I practise in "Prepositions of Time for Deadlines & Schedules — Grammar Exercises"?
Practise by, until, within, in, and on for deadlines, SLAs, and schedules in IT contexts. 5 intermediate exercises with detailed explanations.
How many exercises are in this module?
This module has 8 multiple-choice exercises, each with instant feedback and a full explanation of the correct answer.
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How is this different from reading an article on the same topic?
Articles explain grammar rules in prose; this exercise tests and reinforces those rules through active recall with immediate feedback — the two work best together.
Who writes these exercises?
Every exercise is written by the CoderSlingo team, drawing on real workplace English used in IT roles, then reviewed for accuracy and clarity.