Using Commas to Set Off Appositives and Interrupters

1. Question

   Thousands of “snowballs” from outer space are hitting Earth’s atmosphere every day according to scientists at a recent meeting of the American Geophysical Union in Baltimore.

   A.

   Thousands of “snowballs”

   B.

   from outer space

   C.

   every day

   D.

   according to scientists at a recent meeting of the American Geophysical Union in Baltimore

   Using Commas to Set Off Appositives and Interrupters - In each of the following sentences, choose the appositives and interrupters that should be set off by commas.: Thousands of “snowballs” from outer space are hitting Earth’s atmosphere every day according to scientists at a recent meeting of the American Geophysical Union in Baltimore.

2. Question

   Over billions of years they reported this bombardment of cosmic slush has added vast amounts of water to Earth’s atmosphere and oceans.

   A.

   they reported

   B.

   this bombardment

   C.

   has added vast amounts of water

   D.

   to Earth’s atmosphere

   Using Commas to Set Off Appositives and Interrupters - In each of the following sentences, choose the appositives and interrupters that should be set off by commas.: Over billions of years they reported this bombardment of cosmic slush has added vast amounts of water to Earth’s atmosphere and oceans.

3. Question

   These extraterrestrial snowballs made up of ice and cosmic dust may have played a key role in nurturing life on this planet and perhaps elsewhere in the solar system.

   A.

   made up of ice and cosmic dust

   B.

   may have played

   C.

   in nurturing life

   D.

   and perhaps elsewhere

   Using Commas to Set Off Appositives and Interrupters - In each of the following sentences, choose the appositives and interrupters that should be set off by commas.: These extraterrestrial snowballs made up of ice and cosmic dust may have played a key role in nurturing life on this planet and perhaps elsewhere in the solar system.

4. Question

   They are about forty feet in diameter the size of a small house.

   A.

   about

   B.

   forty feet

   C.

   in diameter

   D.

   the size of a small house

   Using Commas to Set Off Appositives and Interrupters - In each of the following sentences, choose the appositives and interrupters that should be set off by commas.: They are about forty feet in diameter the size of a small house.

5. Question

   These small, cometlike objects unlike large comets are extremely hard to see because they break up into fragments and then vaporize.

   A.

   unlike large comets

   B.

   extremely hard to see

   C.

   into fragments

   D.

   and then vaporize

   Using Commas to Set Off Appositives and Interrupters - In each of the following sentences, choose the appositives and interrupters that should be set off by commas.: These small, cometlike objects unlike large comets are extremely hard to see because they break up into fragments and then vaporize.

6. Question

   Astronomers and physicists however have speculated about their existence since 1986.

   A.

   and physicists

   B.

   however

   C.

   have speculated

   D.

   their existence

   Using Commas to Set Off Appositives and Interrupters - In each of the following sentences, choose the appositives and interrupters that should be set off by commas.: Astronomers and physicists however have speculated about their existence since 1986.

7. Question

   Dr. Louis A. Frank a physicist at the University of Iowa first theorized about them to explain the dark spots he observed in images of Earth’s sunlit atmosphere.

   A.

   a physicist at the University of Iowa

   B.

   first theorized

   C.

   the dark spots

   D.

   in images of Earth’s sunlit atmosphere

   Using Commas to Set Off Appositives and Interrupters - In each of the following sentences, choose the appositives and interrupters that should be set off by commas.: Dr. Louis A. Frank a physicist at the University of Iowa first theorized about them to explain the dark spots he observed in images of Earth’s sunlit atmosphere.

8. Question

   Dr. Frank noticed these spots or atmospheric holes while analyzing data from NASA’s Dynamics Explorer 1 satellite.

   A.

   noticed these spots

   B.

   or atmospheric holes

   C.

   while analyzing

   D.

   Dynamics Explorer 1

   Using Commas to Set Off Appositives and Interrupters - In each of the following sentences, choose the appositives and interrupters that should be set off by commas.: Dr. Frank noticed these spots or atmospheric holes while analyzing data from NASA’s Dynamics Explorer 1 satellite.

9. Question

   NASA’s Polar satellite a veteran space explorer produced more detailed images of these atmospheric holes.

   A.

   satellite

   B.

   a veteran space explorer

   C.

   more

   D.

   of these atmospheric holes

   Using Commas to Set Off Appositives and Interrupters - In each of the following sentences, choose the appositives and interrupters that should be set off by commas.: NASA’s Polar satellite a veteran space explorer produced more detailed images of these atmospheric holes.

10. Question

    Many scientists now believe that these snowballs are hitting Earth’s outer atmosphere at an incredible rate of five to thirty a minute or up to 43,000 a day.

    A.

    now believe

    B.

    that these snowballs

    C.

    Earth’s outer atmosphere

    D.

    or up to 43,000 a day

    Using Commas to Set Off Appositives and Interrupters - In each of the following sentences, choose the appositives and interrupters that should be set off by commas.: Many scientists now believe that these snowballs are hitting Earth’s outer atmosphere at an incredible rate of five to thirty a minute or up to 43,000 a day.