OCG533, Fall 2002
Answers to assignment 5, due 18 September 2002
Structure of sentences IV: Restrictive vs. nonrestrictive modification

Modified Exercise 14-1. Restrictive and nonrestrictive modifiers.
     
Here are ten examples of misused or ambiguous restrictive or nonrestrictive modifiers taken from GSO student abstracts and the literature. Explain what is wrong with each sentence and rewrite it to convey the meaning intended (if you can determine it).

      1. [Scyliorhinus retifer’s] small size and ability to thrive in captivity make it an excellent subject for laboratory studies which can not be done with most other shark species.
     
Problem: Restrictive modification implies that this shark can substitute for only certain laboratory studies. Should be written nonrestrictively.
     
Revision: Add comma before which. [Scyliorhinus retifer’s] small size and ability to thrive in captivity make it an excellent subject for laboratory studies, which cannot be done with most other shark species.

      2. This model is composed of a stack of constant density layers, making it well suited to considering the motion of isopycnal, Lagrangian particles.
     
Problem: Comma should not come between “isopycnal” and “Lagrangian,” because not all isopycnal particles are Lagrangian (or the reverse). [Recursive (restrictive) structure should be used instead of coordinate structure.]
     
Revision: Remove comma: …the motion of isopycnal Lagrangian particles.

      3. For both solids, Sh’ first increased or stayed the same and then decreased with increasing θn while Shapt generally decreased with decreasing θn.
     
Problem: The trailing subordinate clause while… is written as a restrictive modifier of the preceding verb phrase first increased or stayed the same and then decreased with increasing θn. It is actually a clausal modifier. While here means whereas, not during the time that.
     
Revision: Separate the trailing clause from the main clause by a comma to show that it is not a restrictive modifier. For both solids, Sh’ first increased or stayed the same and then decreased with increasing θn, while Shapt generally decreased with decreasing θn.
     
Revision 2: Replace while with whereas. For both solids, Sh’ first increased or stayed the same and then decreased with increasing θn, whereas Shapt generally decreased with decreasing θn.

      4. United States Federal Regulations, required for compliance with the Hazardous and Solid Waste Act, direct the permittee to propose Media Protection Standards for hazardous chemicals that may have been released from their facility.
     
Problem: Nonrestrictive required for compliance with the Hazardous and Solid Waste Act means nonsensically that all United States Federal Regulations are required for compliance with the Hazardous and Solid Waste Act.
     
Revision: Remove commas. United States Federal Regulations required for compliance with the Hazardous and Solid Waste Act direct the permittee to propose Media Protection Standards for hazardous chemicals that may have been released from their facility.

      5. The Mid-Atlantic Ridge in the North Atlantic between 28 N and 70 N overlies two geochemically distinct mantle domains dominated by the Iceland and Azores mantle plumes.
     
Problem 1: The adjectival prepositional phrase in the North Atlantic is written to modify The Mid-Atlantic Ridge restrictively, meaning that there is more than one Mid-Atlantic Ridge, and that only the one in the North Atlantic is being discussed here.
     
Problem 2: Alternatively, the adjectival prepositional phrase between 28 N and 70 N could be viewed as restrictively modifying just the North Atlantic, which also would be nonsensical.
     
Revision: Eliminate the redundant in the North Atlantic and begin the sentence with Between 28 N and 70 N, as follows: Between 28 N and 70 N, the Mid-Atlantic Ridge overlies two geochemically distinct mantle domains dominated by the Iceland and Azores mantle plumes.
     
Revision 2: Add individually to show that one plume goes with one domain: Between 28 N and 70 N, the Mid-Atlantic Ridge overlies two geochemically distinct mantle domains dominated individually by the Iceland and Azores mantle plumes.

      6. Massachusetts Bay had the highest human population density of 8.1 persons ha-1.
     
Problem: The closing prepositional phrase of 8.1 persons ha-1 is nonsensically written as a restrictive postmodifier of the verb phrase had the highest human population density.
     
Revision: Make the phrase nonrestrictive by preceding it with a comma: Massachusetts Bay had the highest human population density, of 8.1 persons ha-1.
     
Revision 2: Better yet, remove of: Massachusetts Bay had the highest human population density, 8.1 persons ha-1.

      7. The fastest growing unstable modes are always the lowest modes having an amplitude maximum near 50 m depth.
     
Problem: The participial phrase having an amplitude maximum near 50 m depth modifies the lowest modes restrictively, meaning the lowest modes [of all the modes] that have amplitude maxima near 50 m depth. It should be written nonrestrictively.
     
Revision: Make the phrase nonrestrictive by inserting a comma: the lowest modes, having an amplitude maximum near 50 m depth. Better English: the lowest modes, whose amplitude maximum is found near 50 m depth.

      8. Constraints on physical conditions within the 1883 magma chamber have been determined from volatile concentrations within melt inclusions and plagioclase-liquid equilibria indicating a minimum total pressure of 1.0–1.5 kbar.
     
Problem: Final participial phrase indicating a minimum total pressure of 1.0–1.5 kbar may well refer to volatile concentrations and plagioclase-liquid equilibria, or perhaps to even the entire clause.
     
Revision: Add comma before final participial phrase: Constraints on physical conditions within the 1883 magma chamber have been determined from volatile concentrations within melt inclusions and plagioclase-liquid equilibria, indicating a minimum total pressure of 1.0–1.5 kbar.

      9. However, DOC concentrations varied by as much as a factor of three over spatial and temporal scales suggesting a relatively dynamic DOC pool.
     
Problem: The restrictive suggesting a relatively dynamic DOC pool incorrectly means that spatial and temporal scales suggest a relatively dynamic DOC pool. The phrase suggesting a relatively dynamic DOC pool should modify the entire independent clause.
     
Revision: Add comma before participial phrase: However, DOC concentrations varied by as much as a factor of three over spatial and temporal scales, suggesting that the DOC pool was relatively dynamic.
     
Revision 2: Also rearrange modifiers in predicate: However, DOC concentrations varied spatially and temporally by as much as a factor of three, suggesting that the DOC pool was relatively dynamic.

      10. It is also possible that these shifts reflect an increase in the relative contribution of petrol lead emitted in East and Central European countries where local emissions are much higher and the isotopic composition of lead is consistent with the observed changes in Paris and Oslo.
     
Problem: Restrictive subordinate clause where local emissions… means that only some of the East and Central European countries have higher local emissions, etc., when all the countries are being referred to.
     
Revision. Insert comma before the clause to make it properly nonrestrictive: It is also possible that these shifts reflect an increase in the relative contribution of petrol lead emitted in East and Central European countries, where local emissions are much higher and the isotopic composition of lead is consistent with the observed changes in Paris and Oslo.

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