Future Perfect vs. Future Continuous – English Grammar Exercises for B2

1 (a) will be drilling

• Why it is correct (The Key): “By this time next month” designates a specific point in the future. The adverb “constantly” emphasizes that the action of drilling will be actively in progress.
• Error Analysis: (c) will have drilled (Meaning Trap: Implies the machines have finished drilling, but “constantly” requires an ongoing tense). (b) will drill (Common Mistake: Misses the ongoing nuance). (d) will be drill (Structural Error).

2 (d) will have spent

• Why it is correct (The Key): “By 2028” acts as a deadline. Generating over $5 billion is an accumulated total that will be entirely completed prior to this deadline.
• Error Analysis: (a) will be spending (Meaning Trap: Fails to express the final calculated sum needed for the review). (b) will spend (Common Mistake). (c) will have spend (Structural Error: The past participle of ‘spend’ is ‘spent’).

3 (b) will be laying

• Why it is correct (The Key): “At exactly midnight tonight” points to a precise moment. The night-shift workers will be actively in the middle of their task.
• Error Analysis: (c) will have laid (Meaning Trap: Implies the task is finished before midnight, contradicting the nature of night-shift work in progress). (d) will lay (Common Mistake). (a) will laying (Structural Error).

4 (d) will have finished

• Why it is correct (The Key): “By the time the ribbon-cutting ceremony takes place” is the deadline. The construction must be 100% completed before the inauguration can happen.
• Error Analysis: (c) will be finishing (Meaning Trap: If they are still finishing, the ceremony cannot logicially take place). (a) will finish (Common Mistake). (b) will have finish (Structural Error).

5 (a) will be monitoring

• Why it is correct (The Key): “During the entire summer” describes an extended timeframe. “Monitoring” will be a continuous, ongoing process throughout that period.
• Error Analysis: (c) will have monitored (Meaning Trap: Ignores the continuous nature indicated by “During”). (b) will monitor (Common Mistake). (d) will be monitor (Structural Error).

6 (c) will have tested

• Why it is correct (The Key): “Before the first passenger train officially departs” acts as a strict deadline. The testing protocol must be completely finished beforehand to ensure safety.
• Error Analysis: (b) will be testing (Meaning Trap: If inspectors are still testing, the train cannot depart). (a) will test (Common Mistake). (d) will have testing (Structural Error).

7 (c) will be holding

• Why it is correct (The Key): “At 10 AM tomorrow” is a specific time. The mayor will be actively in the middle of giving the press conference.
• Error Analysis: (b) will have held (Meaning Trap: If the conference is already over at 10 AM, there is no point in noting the time for the readers). (d) will hold (Common Mistake). (a) will holding (Structural Error).

8 (a) will have completed

• Why it is correct (The Key): “By December next year” is a deadline. “A total of 50 miles” is a measurable achievement that must be fully finished prior to this date.
• Error Analysis: (c) will be completing (Meaning Trap: You cannot actively be completing exactly 50 miles in one single moment; it is a cumulative accomplishment). (b) will complete (Common Mistake). (d) will have complete (Structural Error).

9 (d) will be pouring

• Why it is correct (The Key): “While citizens are sleeping” establishes a parallel timeframe. The heavy machinery will be pouring concrete continuously at the exact same time.
• Error Analysis: (b) will have poured (Meaning Trap: Breaks the parallel structure, implying the pouring is finished before the citizens even sleep). (c) will pour (Common Mistake). (a) are will pour (Structural Error).

10 (d) will have understood

• Why it is correct (The Key): “By the grand opening” acts as a deadline requiring the Future Perfect. The verb “understand” is a stative verb representing a completed state of mind.
• Error Analysis: (b) will be understanding (Common Mistake: Incorrectly applying the continuous tense to a stative verb). (a) will understand (Meaning Trap: Misses the “completed by a deadline” aspect of the sentence). (c) will have understand (Structural Error).

11 (b) have checked

• Why it is correct (The Key): In future time clauses beginning with until, before, when, or once, the future tense (“will”) is forbidden. You must use the Present Perfect (or Present Simple) to emphasize that the condition must be fulfilled first.
• Error Analysis: (a) will have checked (Common Mistake: Using ‘will’ in an ‘until’ clause). (d) will be checking (Structural Error/Meaning Trap). (c) will check (Common Mistake).

12 (d) will have transformed

• Why it is correct (The Key): “By the end of this decade” is a deadline. The transformation of the commute will be a completely established reality by that point.
• Error Analysis: (a) will be transforming (Meaning Trap: Fails to capture the finality of the architectural milestone). (c) will transform (Common Mistake). (b) will have transform (Structural Error).

13 (d) will be complaining

• Why it is correct (The Key): “Next Monday morning” designates a specific future time. Commuters will be in the ongoing state of complaining.
• Error Analysis: (a) will have complained (Meaning Trap: Implies they finish complaining before Monday morning, which is illogical). (b) will complain (Common Mistake). (c) will be complain (Structural Error).

14 (a) will have ended

• Why it is correct (The Key): “By the time the next issue… is published” serves as a completion deadline for the disruptive digging phase.
• Error Analysis: (b) will be ending (Meaning Trap: If it is still ending, the disruption is not over, breaking the author’s reassurance). (d) will end (Common Mistake). (c) will have end (Structural Error).

15 (a) will be running / won’t have paid

• Why it is correct (The Key): “At this time next year” points to an ongoing process (will be running). However, at that point, the city’s action of paying off the debt will NOT be completed (won’t have paid).
• Error Analysis: (c) will have run / won’t be paying (Meaning Trap: Reverses the logic completely). (b) will run / won’t pay (Common Mistake). (d) will be running / won’t have pay (Structural Error).

16 (b) will have been excavated

• Why it is correct (The Key): “By the time…” requires the Future Perfect. Because the “10,000 tons of earth” receives the action, the Passive Voice Future Perfect is required (will have been excavated).
• Error Analysis: (c) will have excavated (Meaning Trap: Active voice implies the earth dug itself out). (a) will be excavating (Meaning Trap: Active voice + misses the deadline completion). (d) will be excavated (Common Mistake: Misses the perfect aspect required by ‘by’).

17 (d) will the metro have reshaped / will have created

• Why it is correct (The Key): Advanced syntax. Starting a sentence with “Not only” requires subject-auxiliary inversion (will the metro have). “By 2030” applies to both clauses, meaning both achievements will be 100% complete (will have reshaped / will have created).
• Error Analysis: (a) the metro will have reshaped… (Common Mistake: Fails to invert after “Not only”). (b) will the metro be reshaping… (Meaning Trap: Misses the completion required by the deadline “by 2030”). (c) will have the metro reshaped (Structural Error: Incorrect inversion order).

18 (a) will be stressing / will have

• Why it is correct (The Key): “During the testing phase” describes an ongoing action (will be stressing). The verb “have” (meaning possessing access) is a stative verb and cannot take the continuous form (will have).
• Error Analysis: (c) will be stressing / will be having (Common Mistake: Forcing the stative verb ‘have’ into the continuous tense). (b) will have stressed / will be having (Meaning Trap: Perfect tense doesn’t fit the “During” ongoing context). (d) will stress / will have had (Structural Error).

19 (c) will have worked / will be

• Why it is correct (The Key): “By 2029” requires the Future Perfect to measure an accumulated duration of “a decade” (will have worked). Consequently, he will exist in the ongoing state of being an expert (Future Simple for the stative verb ‘be’ -> will be).
• Error Analysis: (b) will be working / will have been (Meaning Trap: Fails to capture the accumulated 10-year timeframe first). (a) will work / will be (Common Mistake). (d) will have worked / will be being (Structural Error: The verb ‘be’ for a state/profession cannot be continuous).

20 (b) has been issued / will open

• Why it is correct (The Key): “Once” functions like “when” or “after,” introducing a time clause where “will” is forbidden. We use the Present Perfect Passive to show the certificate must be fully processed first (has been issued). The main clause follows with a standard future action (will open).
• Error Analysis: (a) will be issued / will open (Common Mistake: Using ‘will’ in an ‘once’ time clause). (c) will have been issued / will be opening (Meaning Trap: Incorrect tense usage in both clauses). (d) is issued / will have opened (Meaning Trap: Reverses the chronological logic).

1. Future Perfect for Megaproject Milestones: Use will have + past participle (V3/ed) when you have deadline keywords like by 2028, by the time it opens, before the train departs. This emphasizes that a construction phase, an accumulated cost, or a safety check has been fully completed before that specific deadline.
2. Future Continuous for Ongoing Construction: Use will be + V-ing to describe the disruptive processes that will be taking place at a fixed future time or over a duration (e.g., during the summer, tomorrow at midnight, at this time next year).
3. The Stative Verbs Trap: Be extremely cautious with stative verbs like understand, have (access), be. Even if you are describing an ongoing state in the future, they must remain in the simple form (will understand, will have), NEVER in the continuous form like will be understanding or will be having.
4. The Time/Condition Clauses Trap: After time conjunctions like once, when, until, by the time, before, you MUST NOT use the future tense (“will”). You must use the Present Simple or Present Perfect to express the prerequisite condition (e.g., until they have checked the system).
5. Inversion with Negative Adverbs: To elevate the tone of a professional review, when starting a sentence with a negative phrase like Not only, you must invert the auxiliary verb and the subject: Not only will the metro have reshaped… (NOT Not only the metro will have reshaped…).