Dengue Transmission in the United States Is Increasingly Local

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

C1. 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

Fill in the blank (dropdown)

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 · Fill in the blank (dropdown)

   Choose the correct option for each blank.

   In the past, many Americans ___ dengue while traveling.

   Choices for blank 1

   1. had been infected with
   2. have been infected with
   3. were being infecting with
   4. had infected by
   Check answers and explanations

   Blank 1

   had been infected with

   Past perfect passive marks infection before return.

2. Question 2 · Fill in the blank (dropdown)

   Choose the correct option for each blank.

   The pattern changed, ___ the risk more directly to local communities.

   Choices for blank 1

   1. tying
   2. tied
   3. to tying
   4. having tie
   Check answers and explanations

   Blank 1

   tying

   The participle phrase expresses the result of the change.

3. Question 3 · Fill in the blank (dropdown)

   Choose the correct option for each blank.

   The distinction concerns how infections arise, ___ where symptoms begin.

   Choices for blank 1

   1. rather than simply
   2. rather simply than
   3. rather than to simply
   4. rather simply to
   Check answers and explanations

   Blank 1

   rather than simply

   “Rather than” sets up the intended contrast between ideas.

4. Question 4 · Fill in the blank (dropdown)

   Choose the correct option for each blank.

   If local transmission ___, dengue may become more persistent.

   Choices for blank 1

   1. continues
   2. will continue
   3. would continue
   4. continued
   Check answers and explanations

   Blank 1

   continues

   The first conditional uses present simple in its if-clause.

5. Question 5 · Fill in the blank (dropdown)

   Choose the correct option for each blank.

   The facts establish ___ local transmission accounts for most current spread.

   Choices for blank 1

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

   Blank 1

   that

   A that-clause correctly completes the verb “establish.”

6. Question 6 · Fill in the blank (dropdown)

   Choose the correct option for each blank.

   The earlier pattern, along with the current shift, ___ a meaningful change.

   Choices for blank 1

   1. describes
   2. describe
   3. are describing
   4. have described
   Check answers and explanations

   Blank 1

   describes

   The singular subject “pattern” takes a singular verb.

7. Question 7 · Fill in the blank (dropdown)

   Choose the correct option for each blank.

   The account is cautious, ___ it notes limits in the available facts.

   Choices for blank 1

   1. because
   2. despite
   3. whereas
   4. unless
   Check answers and explanations

   Blank 1

   because

   “Because” introduces the reason for the account’s caution.

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.