Sunday, January 21, 2007

That vs which, and numbers!

When do you use 'that' and when do you use 'which'?

When do you spell out numbers? I was reading one of my science textbooks, and they're not very consistent. "Sixty-one of the 64 codons code for the twenty common amino acids."

Lily posted a comment to my previous question:

What about words such as "unfortunately," "absolutely," "surprisingly," etc...? Is it all right to use an adverb at the beginning of the sentence as long as there is a verb it may be modifying later on in the sentence? Do adverbs have to be next to what it modifies?
Unfortunately, he gambled all his money away.
(Correct? to gamble unfortunately?)
Unfortunately, he did not win any money. (Incorrect? Nothing to modify?)


Pat said...

Generally speaking, "that" is used for restrictive clauses and "which" for nonrestrictive ones. Here are some examples:

NONRESTRICTIVE (does not restrict the meaning of the noun it modifies)

Lord of the Rings, which I really enjoyed, is my favorite movie.

My trip to Vancouver, which occurred in spring 2005, was wonderful.

McKinley High School, which is located on King Street, was once called Tokyo High.

RESTRICTIVE (restricts the meaning of the noun it modifies)

The movie that I really enjoyed is Lord of the Rings.

Please eat only the cookies that are in the jar above the fridge.

Is the dog that is tied to the parking meter yours?

For exercises and a discussion of restrictive and nonrestrictive clauses, see pages 123 to 129 of your textbook.

* * * * * * * * *

Several sections of Chicago Manual of Style are devoted to discussions of the treatment of numbers. On pages 172 and 173 of your textbook, the different style manuals are compared on this point.

The example you cite does seem to have inconsistencies. "Sixty-one" is a number that appears at the beginning of a sentence, so it is correct to spell it out; however, using digits for 64 but not 20 seems odd.

Pat said...

I should have said something about when numbers should be spelled out. In general, they should in these cases:

1. if used at the beginning of sentences;
2. if rounded off ("I paid a thousand dollars in taxes last year");
3. if they are not critical to the meaning of the passage in which they appear ("I went home at ten o'clock and fell asleep on the couch"); and
4. if they are estimates ("Six or seven cars were involved in the pile-up on the freeway").

Pat said...

In response to Lily's comment, let me quote from a section of the APA (American Psychological Assocation) manual:

Adverbs can be used as introductory or transitional words. Adverbs modify verbs, adjectives, and other adverbs and express manner or quality. Some adverbs, however—such as fortunately, similarly, certainly, consequently, conversely, and regrettably—can also be used as introductory or transitional words as long as the sense is confined to, for example, "it is fortunate that" or "in a similar manner." Use adverbs judiciously as introductory or transitional words. Ask yourself whether the introduction or transition is needed and whether the adverb is being used correctly.

The adverbial clause most often misused is more importantly. Importantly means "in an important way," not "this is important."

Incorrect: More importantly, the total amount of available long-term memory activation, and not the rate of spreading activation, drives the rate and probability of retrieval.

Correct: More important, the total amount of available…

Correct: Expressive behavior and autonomic nervous system activity have also figured importantly…

(For a link to a page on the manual, see upper-right corner of the blog.)

Ritchie Mae said...

That vs. which.

Which would be more effective, formal, etc.?

For example, this particular sentence can be written in two ways:

Restriction endonucleases are bacterial enzymes, which cleave double-stranded DNA into smaller, more manageable fragments.


Restriction endonucleases are bacterial enzymes that cleave double stranded DNA into smaller more manageable fragments.

Pat said...

Using the restrictive clause narrows the category of bacterial enzymes down to restriction endonucleases, so I would use that.