A Strange Detector Signal Renews Questions About Dark Matter

Study the questions and tasks

Work through the material below, or start the interactive practice above to complete an attempt. Try the exercises before opening any answer or transcript sections, then use them to review your work.

Practice level

B2. Try this level if you can follow the instructions and understand most of the language; choose an earlier level if you need more support.

Question formats

Single choice

How to approach this practice

Read the complete sentence and notice the subject, verb form, time reference and word order before answering.

1. Question 1 · Single choice

   Choose one answer.

   Choose the correct form: The signal _____ fresh discussion about dark matter.

   1. has prompted
   2. prompting
   3. prompt
   4. have prompt
   Check answers and explanations

   Answer

   has prompted

   The present perfect connects a past event with its current effect.

2. Question 2 · Single choice

   Choose one answer.

   Choose the best modal: The event _____ prove important, but certainty is impossible now.

   1. could
   2. must
   3. ought
   4. would have
   Check answers and explanations

   Answer

   could

   “Could” expresses possibility without claiming that the event will matter.

3. Question 3 · Single choice

   Choose one answer.

   Choose the correct relative clause: The detector is an instrument _____ scientists designed to observe specific events.

   1. that
   2. whose
   3. where
   4. what
   Check answers and explanations

   Answer

   that

   “That” correctly introduces the defining relative clause describing the instrument.

4. Question 4 · Single choice

   Choose one answer.

   Choose the correct form: Researchers must consider both possibilities as they _____ what happened.

   1. assess
   2. assessed
   3. are assessed
   4. will assessing
   Check answers and explanations

   Answer

   assess

   The present simple follows “as” for a general process happening during assessment.

5. Question 5 · Single choice

   Choose one answer.

   Choose the best connector: The signal attracted attention _____ it did not provide a final answer.

   1. although
   2. because of
   3. unless
   4. so that
   Check answers and explanations

   Answer

   although

   “Although” introduces a contrast between attention and lack of certainty.

6. Question 6 · Single choice

   Choose one answer.

   Choose the correct passive form: The unusual recording _____ by a detector in South Dakota.

   1. was recorded
   2. recorded
   3. has recording
   4. was recording
   Check answers and explanations

   Answer

   was recorded

   The passive voice emphasizes the recording rather than the unnamed recorder.

7. Question 7 · Single choice

   Choose one answer.

   Choose the correct reported possibility: Scientists may ask whether another explanation _____ more convincing.

   1. might be
   2. must being
   3. has been to
   4. would being
   Check answers and explanations

   Answer

   might be

   “Might be” appropriately reports a possible present evaluation.

What to review next

After checking an answer, explain the rule in your own words and write a new sentence using the same pattern. Revisit any rules you could not explain.

A focused practice result shows how you did on these tasks. Use several activities across skills to decide what to study next; one practice score does not certify an overall CEFR level.