By vs. Until – English Grammar Exercises for B2
Read the technology corporation’s official email announcing the deprecation of their legacy software. Choose the best option to complete the sentences.
1 “Please be advised that our legacy software, Version 40, will remain active and fully functional ______ December 31st.”
(a) by
(b) until
(c) within
(d) at
2 “To avoid any permanent data loss, all enterprise users must migrate their data to the new cloud servers ______ the end of the month.”
(a) until
(b) for
(c) by
(d) during
3 “Our dedicated engineering team will continue to offer security patches and technical support ______ next Friday.”
(a) until
(b) by
(c) to
(d) in
4 “You are required to download and install the newest client interface ______ the official deprecation deadline.”
(a) until
(b) during
(c) at
(d) by
5 “We highly recommend that you do not delete your old local archives ______ the cloud migration process is 100% complete.”
(a) by
(b) within
(c) until
(d) since
6 “If we do not receive your digital consent to the new Terms of Service ______ November 15th, your account will be suspended.”
(a) until
(b) to
(c) by
(d) as
7 “The legacy authentication servers will be kept online ______ the final transition phase officially concludes.”
(a) by
(b) until
(c) in
(d) by the time
8 “We expect all our valued customers to successfully transition to the upgraded platform ______ the first quarter of next year.”
(a) until
(b) by
(c) for
(d) at
9 “You can safely keep using your current API keys ______ we officially revoke them next month.”
(a) until
(b) by
(c) by the time
(d) within
10 “Please export your customized user settings ______ Monday morning, as they cannot be recovered afterward.”
(a) until
(b) during
(c) in
(d) by
11 “The current dashboard will stay accessible to all administrators ______ midnight.”
(a) by
(b) until
(c) at
(d) within
12 “______ the time we pull the plug on the old servers, all unsaved project files will be permanently erased.”
(a) Until
(b) In
(c) By
(d) To
13 “We will postpone the final system purge ______ all VIP corporate clients have successfully transferred their databases.”
(a) by
(b) until
(c) by the time
(d) within
14 “Your current premium license is valid ______ January 1st, meaning you must renew it on the new platform ______ that exact date.”
(a) by / until
(b) until / by
(c) by / by
(d) until / until
15 “If you delay the necessary system update ______ next month, your network will be highly vulnerable to external security breaches.”
(a) until
(b) during
(c) by
(d) since
16 “Let’s keep the older communication channels open ______ the new chat application is fully deployed across all departments.”
(a) by
(b) until
(c) to
(d) in
17 “Every user profile must be manually verified and authenticated ______ the end of this transition session.”
(a) until
(b) by
(c) for
(d) at
18 “We will not officially shut down the legacy application ______ the new version is proven to be completely stable.”
(a) by
(b) until
(c) by the time
(d) as
19 “I need all department heads to wrap up their final software evaluations ______ 5:00 PM today so we can proceed with the shutdown.”
(a) until
(b) during
(c) by
(d) to
20 “We cannot guarantee data integrity if you wait ______ the last minute; please complete your upgrade ______ this coming weekend.”
(a) by / until
(b) until / until
(c) until / by
(d) by / by
ANSWER KEY & EXPLANATIONS
1 (b) until
- Why it is correct (The Key): “Remain active” is a continuous state. Until is used to show how long an ongoing state or action continues before it stops.
- Error Analysis: (a) by (Common Mistake: You cannot continuously “remain active” by a time; by is for single, completed actions). (c) within (Structural Error: Requires a duration, like “within a month”). (d) at (Meaning Trap: “At” means it becomes active exactly on December 31st, contradicting the “remain” logic).
2 (c) by
- Why it is correct (The Key): “Migrate your data” is a completed action representing a strict deadline. It means the action must be finished no later than the end of the month.
- Error Analysis: (a) until (Common Mistake: You cannot continuously “migrate” the final completion over a period of time). (b) for (Structural Error). (d) during (Meaning Trap: Lacks the deadline enforcement required by the EOL notice).
3 (a) until
- Why it is correct (The Key): “Continue to offer” indicates an ongoing service. This service will last up to next Friday.
- Error Analysis: (b) by (Common Mistake: Continuing is not a momentary completion). (c) to (Structural Error). (d) in (Structural Error).
4 (d) by
- Why it is correct (The Key): “Download and install” is a momentary action of completion. The company sets a deadline for this to happen.
- Error Analysis: (a) until (Common Mistake). (b) during (Meaning Trap: Too vague, removing the sense of a strict deadline). (c) at (Meaning Trap: “At” means exactly at the deadline moment, whereas “by” means it can be done anytime before).
5 (c) until
- Why it is correct (The Key): When a punctual action is negated (“do not delete”), it creates a continuous state of keeping the files. Until marks the end of this waiting period.
- Error Analysis: (a) by (Common Mistake). (b) within (Structural Error). (d) since (Structural Error: Refers to the starting point in the past, not the end point in the future).
6 (c) by
- Why it is correct (The Key): “Receive your digital consent” is a completed action. The company must have it before the deadline hits.
- Error Analysis: (a) until (Common Mistake: They cannot continuously “receive” a single signature). (b) to (Structural Error). (d) as (Structural Error).
7 (b) until
- Why it is correct (The Key): “Be kept online” is an ongoing state. The servers will maintain this state up to the time the transition concludes.
- Error Analysis: (a) by (Common Mistake). (c) in (Structural Error). (d) by the time (Meaning Trap: Grammatically incorrect here without a perfect tense).
8 (b) by
- Why it is correct (The Key): “Transition” (as a verb meaning to successfully complete the move) is a punctual achievement representing a strict deadline.
- Error Analysis: (a) until (Common Mistake). (c) for (Structural Error). (d) at (Meaning Trap).
9 (a) until
- Why it is correct (The Key): “Keep using” is explicitly an ongoing action.
- Error Analysis: (b) by (Common Mistake). (c) by the time (Structural Error). (d) within (Structural Error).
10 (d) by
- Why it is correct (The Key): “Export your settings” indicates a completed action. It must reach this state before Monday morning.
- Error Analysis: (a) until (Common Mistake). (b) during (Meaning Trap). (c) in (Structural Error).
11 (b) until
- Why it is correct (The Key): “Stay accessible” is a continuous state.
- Error Analysis: (a) by (Common Mistake). (c) at (Meaning Trap). (d) within (Structural Error).
12 (c) By
- Why it is correct (The Key): “By the time” introduces a deadline clause. It highlights that a condition (files being erased) will be fully realized before the moment they pull the plug.
- Error Analysis: (a) Until (Common Mistake). (b) In (Structural Error). (d) To (Structural Error).
13 (b) until
- Why it is correct (The Key): “Postpone” initiates a state of waiting or delaying an action. You maintain this delay until the prerequisite condition (clients transferring databases) is met.
- Error Analysis: (a) by (Common Mistake). (c) by the time (Meaning Trap: Clunky and alters the grammatical requirement of the dependent clause). (d) within (Structural Error).
14 (b) until / by
- Why it is correct (The Key): “Is valid” is a continuous state of the license (until January 1st). “Renew it” is a conclusive achievement representing a deadline (by that exact date).
- Error Analysis: (a) by / until (Meaning Trap: Reverses the logic). (c) by / by (Common Mistake). (d) until / until (Common Mistake).
15 (a) until
- Why it is correct (The Key): “Delay” means to push an action back, creating an ongoing state of waiting. You wait until next month.
- Error Analysis: (c) by (Common Mistake). (b) during (Meaning Trap). (d) since (Structural Error).
16 (b) until
- Why it is correct (The Key): “Keep open” is an ongoing state maintained up to the point of full deployment.
- Error Analysis: (a) by (Common Mistake). (c) to (Structural Error). (d) in (Structural Error).
17 (b) by
- Why it is correct (The Key): “Be manually verified” is a momentary action of completion. It must be completed before the transition session ends.
- Error Analysis: (a) until (Common Mistake: You cannot continuously verify a single profile). (c) for (Structural Error). (d) at (Meaning Trap).
18 (b) until
- Why it is correct (The Key): The negative “will not shut down” establishes a state of keeping the app alive. This waiting lasts until the new version is stable.
- Error Analysis: (a) by (Common Mistake). (c) by the time (Meaning Trap). (d) as (Structural Error).
19 (c) by
- Why it is correct (The Key): “Wrap up” (finish) is a punctual action. 5:00 PM is the strict deadline to complete it.
- Error Analysis: (a) until (Common Mistake: You cannot continuously wrap up over a long period). (b) during (Meaning Trap). (d) to (Structural Error).
20 (c) until / by
- Why it is correct (The Key): “Wait” is a continuous process of doing nothing (until the last minute). “Complete your upgrade” is the punctual, final action representing a deadline (by this coming weekend).
- Error Analysis: (a) by / until (Meaning Trap: Reverses the logic completely). (b) until / until (Common Mistake: You cannot continuously complete the upgrade). (d) by / by (Common Mistake: You cannot keep waiting “by” a time).
GRAMMAR POINTS TO REMEMBER
1 UNTIL (For the Duration of a Service):
- Use Until to define the duration of an ongoing action or state. It answers the question: How long will this software or service keep working before it stops?
- Key Verbs: remain (active), keep (using), stay (accessible), continue, wait, delay, postpone, be valid.
- Example: “Version 40 will remain active until December.” (The software is in a continuous state of working spanning the whole time).
2 BY (For Deadlines & Upgrades):
- Use By to indicate a strict deadline for a completed action. It answers the question: What is the latest possible time I can perform this action? (It means “no later than”).
- Key Verbs: upgrade, migrate, download, export, submit, wrap up, complete, transition.
- Example: “You must migrate your data by Friday.” (The migration is an action that must be fully completed before Friday arrives).
3 The “Do Not” Waiting Rule in Tech:
- When a company tells you not to do a momentary action (e.g., “Do not delete your files,” “Do not shut down the app”), it creates a continuous state of keeping things as they are. Therefore, you must use until.
- Example: “Do not uninstall the old app until the new one is fully synced.” (Maintain the old app up to that exact moment).
4 BY THE TIME (For Pre-existing Conditions):
- Use By the time + Clause to express that one event will already be finished before another event happens.
- Example: “By the time the deadline arrives, your old data will be erased.”