Past Simple Tense & Past Continuous Tense

1. As the delegates were making their way into the conference hall, a power failure ---- the entire building into darkness for almost twenty minutes.

Simple Present & Present Continuous Tense

2. Nowadays even the most cautious geologists ---- the theory of plate tectonics to be beyond serious dispute, although the idea was dismissed as fantasy for the best part of half a century.

Present Perfect Tense & Present Perfect Continuous Tense

3. The manuscript on display in the second hall is the oldest complete copy of the epic that ---- to the public anywhere in Europe.

Present Perfect Tense & Present Perfect Continuous Tense

4. Although the volcano ---- ash continuously for the past six weeks, the monitoring team ---- no significant change in the underground pressure readings so far.

Types of Pronouns

5. The reading habits of adolescents who have grown up with smartphones differ in almost every measurable respect from ---- of the generation that reached adulthood before the internet became widely available.

Present Perfect Tense & Present Perfect Continuous Tense

6. Professor Demirsoy ---- the current director of the institute since the two of them were graduate students in Vienna, which is why her recommendation carries so much weight in the department.

Types of Pronouns

7. The 1783 eruption of Laki, ---- released enough sulphur dioxide to disrupt harvests across northern Europe for two consecutive seasons, is still used to calibrate volcanic forcing in climate models.

Future Tenses

8. The department's field trip starts on Monday morning, so this time next week the geology students ____ rock samples along the eastern ridge instead of sitting in the lecture hall.

Future Tenses

9. Unless the funding agency ____ its decision on the grant applications before the end of the month, the laboratory will have to suspend the two clinical trials that are already under way.

Tense Agreement in Time Clauses

10. ---- had the newly built bridge been opened to traffic ---- inspectors detected worrying cracks in one of its main support columns.

Modals Verbs of Ability & Possibility

11. Her coat was still hanging behind the door and her coffee cup had been left half full; since nothing else could account for the state of the office, the researcher ---- the building in a great hurry.

Modals Verbs of Obligation, Necessity & Prohibition

12. If the research team wants its grant to be renewed for a second term, it ---- the interim report before Friday; the funding body is notorious for rejecting late submissions without any further correspondence.

Tense Agreement in Time Clauses

13. No sooner ---- their preliminary assessment of the fault line than the provincial authorities ordered the evacuation of three nearby villages.

Tense Agreement in Time Clauses

14. The ethics board will not authorise the second phase of the clinical trial until the independent review panel ---- its evaluation of the preliminary safety data.

Simple Present & Present Continuous Tense

15. Whenever he prepares a béarnaise for the tasting menu, the chef ---- the sauce at least four times, since he insists that it ---- unpleasantly sharp if the vinegar goes into the pan too early.

Present Perfect Tense & Present Perfect Continuous Tense

16. Since the laboratory ---- the automated sequencing protocol in 2019, the number of samples it can process in a single working day ---- more than fourfold.

Tense Agreement in Time Clauses

17. Under the regulations that come into force next January, no construction permit ---- until an independent environmental impact assessment has been submitted to the ministry.

Future Tenses

18. I am afraid I cannot attend the departmental meeting on Friday afternoon; I ____ a group of visiting researchers around the new laboratory, and the timetable was fixed weeks ago.

Past Simple Tense & Past Continuous Tense

19. The photograph captures a single instant in the summer of 1962: children ---- in the square, vendors were shouting their prices, and a tram was crawling past the fountain.

Tense Agreement in Time Clauses

20. By the time the ministry announced its new emission targets last spring, a number of large manufacturers ---- their own carbon-reduction programmes without waiting for any legal obligation.

Modals Verbs of Ability & Possibility

21. The manuscript is written on a type of paper that was not manufactured anywhere in Europe before 1450, which means that the monk to whom it is traditionally attributed, and who died in 1391, ---- it.

Simple Present & Present Continuous Tense

22. I must ask to be left off the programme for Friday morning, as I ---- a delegation of visiting scholars around the excavation trenches at ten, and the arrangement was made weeks ago.

Modals Verbs of Obligation, Necessity & Prohibition

23. Under the laboratory's safety protocol, visitors ---- the culture plates under any circumstances; the document treats this as an absolute prohibition rather than a mere expectation, since even momentary contact can ruin months of work.

Modals Verbs of Obligation, Necessity & Prohibition

24. Ayla ---- the entire dataset by hand over three exhausting weekends; she found out only afterwards that a free conversion tool would have done exactly the same job in a matter of seconds.

Present Perfect Tense & Present Perfect Continuous Tense

25. The number of undergraduates choosing to major in classical philology ---- by almost half since the faculty merged the department with linguistics.

Past Simple Tense & Past Continuous Tense

26. As soon as the preliminary results of the trial were announced, the share price of the biotechnology firm ---- sharply, surprising even the most cautious analysts on the exchange.

Present Perfect Tense & Present Perfect Continuous Tense

27. The manuscript was sent out for review eight months ago, but the editors ---- the authors any feedback ----.

Tense Agreement in Time Clauses

28. While the volunteers ---- water samples from the lower stretch of the river, a sudden rise in the water level forced them to abandon the site.

Future Tenses

29. - The projector in the seminar room has stopped working again, and the guest lecture is due to start in ten minutes.
- Don't panic. I ____ the technical office right now and ask them to send someone up immediately.

Modals Verbs of Ability & Possibility

30. The lights in the observatory dome have been burning since dawn and all three vehicles are still parked outside, which can only mean that the team ---- still analysing the data from last night's session.

Types of Pronouns

31. Most of the referees found ---- hard to believe that a study based on only twelve participants could justify so sweeping a generalisation about the limits of human memory.

Simple Present & Present Continuous Tense

32. The number of applications to the archaeology programme ---- sharply at present, largely because a popular documentary series has drawn public attention to the recent excavations in the region.

Past Simple Tense & Past Continuous Tense

33. ---- the ferry was approaching the harbour, a dense fog ---- so quickly that the captain had to drop anchor offshore and wait until dawn.

Future Tenses

34. When the observatory celebrates its centenary in 2031, its main telescope ____ the northern sky night after night for a hundred years, ever since it was first switched on in the winter of 1931.

Types of Pronouns

35. The two anonymous referees to ---- the manuscript had been sent in the first round both recommended outright rejection, yet the editor chose to invite a substantially revised version.

Types of Pronouns

36. Unlike the earlier prototype, which had to be recharged every two hours, the device now being tested by the engineering team stores most of ---- operating energy in a graphene capacitor.

Modals Verbs of Ability & Possibility

37. The seismic network has recorded unusual tremors beneath the caldera, and volcanologists warn that the mountain ---- at some point within the next decade, though nothing is certain yet.

Types of Pronouns

38. The dean was so dissatisfied with the wording of the final paragraph that she rewrote it ---- instead of returning the whole document to the drafting committee for a third time.

Present Perfect Tense & Present Perfect Continuous Tense

39. Dr. Ateş ---- to the Antarctic research station three times so far, and she is due to fly out there once again in November.

Present Perfect Tense & Present Perfect Continuous Tense

40. The two research groups have been sharing the same climate data set ---- nearly a decade, yet they have published only one joint paper so far.