Exercise 185 — Explanatory Expressions
D. The explanatory relative clause.
Similar to the appositive is the explanatory relative clause. Like an appositive, it is inserted into the sentence for the purpose of explanation and is separated from the rest of the sentence by commas. Because of this similarity, it is sometimes called an appositive relative clause.
Great care must be taken in punctuation to distinguish a clause that may be omitted from the sentence without destroying the meaning from one that may not be omitted. The appositive clause may be omitted. A restrictive clause, because it restricts the meaning of the word it modifies, may not be omitted. Because it is needed for the sake of clearness, it is not separated from the rest of the sentence by commas. To distinguish an appositive clause from a restrictive clause, the former is called a non-restrictive clause.
Notice the difference between the following:
1. The Commonwealth Edison Company, which controls the electric light and power supply of Chicago, was organized in 1907 by the consolidation of the Chicago Edison Company and the Commonwealth Electric Company.
The sentence makes complete sense without the relative clause.
2. The concern that controls the electric light and power supply of Chicago is the Commonwealth Edison Company.
The relative clause must be used to understand the sentence.
In (1) the relative clause gives an additional idea. In (2) it limits or restricts the meaning of the concern. The non-restrictive clause is shown in (1), the restrictive clause in (2).
Dictation to illustrate non-restrictive clauses:
It is estimated that Chicago annually uses 93,450,000 gallons of milk, for which it pays over $28,000,000. To supply this amount 120,000 cows are needed, which are owned by 12,000 dairy farms. Health officers conduct a systematic dairy farm inspection, which has for its purpose the exclusion of diseased milk. Farm owners, who formerly objected to the inspection, now see that cleanliness is profitable. Authorities have discovered that milk, which easily absorbs germs, is dangerous except when produced under sanitary conditions, and now dairies are allowed to sell only clean, pure milk, which is milk given by a healthy cow.
Phrases as well as clauses may be restrictive. In the following sentences decide whether the italicized expressions are restrictive or non-restrictive. State whether they are phrases or clauses. Do any of the sentences need commas?
1. The man wearing the brown coat is my brother.
2. My brother bought a new coat which is brown.
3. The lesson that I take at nine o’clock is English.
4. In English which I take at nine o’clock we are studying punctuation.
5. I am going to work in every city that I visit.
6. I am going to work in any city where I can find employment.
7. I am going to work in Denver where my uncle lives.
8. The house on the hill is the oldest in town.
9. The house that is the oldest in town is used as a museum.
10. The Franklin Museum which occupies the oldest house in town is a very interesting place.
11. The town museum is the place that I like to visit.
12. The chimney that was blown down last night in the storm should have been mended long ago.
13. The old ruined tower which has long been a picturesque sight in the village was blown down last night.
14. We counted ten chimneys that were blown down last night.
15. The stenography system that I studied is Munson’s.
16. I think she uses Munson’s which she considers a good system of stenography.
17. Last year I pursued a course in stenography which I enjoyed very much.
18. The book that we use in class has a brown cover.
19. The only milk that is fit to drink comes from a clean dairy.
20. Systematic inspection has been carried on which has resulted in securing better milk.
Rule 9.—A non-restrictive clause should be separated from the rest of the sentence by commas.