Everything English

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Category : Mechanics

“That” vs. “Which”

“That” is a restrictive, or defining, pronoun, meaning (basically) that it is used in definitional contexts:

  • This is the hat that I wore to the wedding.

Here, “that I wore to the wedding” is a restrictive clause introduced by the restrictive pronoun “that”. The restrictive clause defines the hat as the one worn to the wedding.

(On a side note, you might also see: “This is the hat I wore to the wedding.”)

Whether “which” may also be used as a restrictive, or defining, pronoun is debatable. The previous example could be written as:

  • This is the hat which I wore to the wedding.

However, this construction is used mostly in informal speech. Speakers of formal American English tend to consider “which” a non-restrictive, or non-defining, pronoun to be used in non-restrictive clauses that are set off by commas (in writing) or pauses in speech, as in:

  • This hat, which I wore the wedding, will never be worn again.

The confusion, for some, arises in cases such as the following:

  • The car, which is faster than all the others, will win the race.
  • The car which is faster than all the others will win the race.

In the first example, a specific car is mentioned. It is implied that this car is faster than all the others and is predicted to win the race. In the second example, a general rule is stated – that the fastest car (not this car, but whichever car is fastest) will win the race. The meanings of the sentences are different. Generally, formal American English requires that the second example be written as:

  • The car that is faster than all the others will win the race.

One way to think about the difference between restrictive and non-restrictive clauses – and when to use “which” vs. “that” – is to remove the clause in question from the sentence and see whether the meaning of the sentence changes:

  • 1) The car, which is faster than all the others, will win the race BECOMES 2) The car will win the race.

The meaning doesn’t really change, as we began (1) by stating that “the car” (this car), will win the race – and added, with the sub-clause “which is faster than all the others” that the car happened to be faster than other cars. The fact that the car was faster was not essential to the sentence, whose purpose was to note that the car would win. (In this sense, noting that the car was faster was kind of a “by the way …”)

  • 1) The car that/which is faster than all the others will win the race BECOMES 2) The car will win the race.

In this case, we began (1) by stating a rule: The fastest car will win the race. The clause “that/which is faster than all the others” was essential to the definition of this rule. By removing it, we changed the meaning of the sentence. (2) does not state that the fastest car will win. It says that a specific car (this car) will win.

Generally speaking, the rule is that when a removing a clause from a sentence alters the meaning of that sentence, that clause should off-set by “that”, not “which”. When the meaning of a sentence is unaltered by the removal of a clause, the clause should be off-set by “which”.

Simple Past vs. Present Perfect

The present perfect tense is used to describe actions that took place in the past and continue to be relevant in the present – and, in some cases, actions that took place in the past and continue to take place in the present.

The simple past tense is used to describe actions that took place in the past and no longer take place in the present. It does not convey the same sense of continuity or relevance as the present perfect.

Here’s an example:

  • President Obama has stated his intent to run for a second term of office.

Here, the present perfect is used because the election in which the currently-sitting president will compete has not yet occurred, and so the president’s announcement that he will run is still relevant.

It would not be appropriate to write, “President Obama stated his intent to run for a second term of office,” unless this sentence were situated in a specific context that no longer exists. For example: “On April 4, 2011, President Obama stated in an email to his supporters that he will run for a second term of office.” Here, the simple past is appropriate because the email announcing the president’s intent to run was sent on a day that has ended. Although those who follow the news know that, at the time of this post, the president’s announcement is still relevant and his intent to run ongoing, this is not really important here and should not suggest the use of the present perfect, as the purpose of the sentence is to convey information about events that happened at a specific time in the past – not to imply the continuity of the president’s intent.

Another, perhaps easier example:

  • President Johnson stated his intent to only serve one term in office.

Lyndon B. Johnson was president of the United States from 1963-1969 and served one elected term, at the end of which he decided not to run for another. It would not be appropriate to say, “President Johnson has stated his intent to only serve one term in office,” because his intent is no longer relevant (i.e. does not affect events today). There is no upcoming election in which Johnson could or would complete (he died in 1973).

In academic writing, the simple past and present perfect tenses are often interchangeable, as in:

  • Lee observed the importance of news media coverage.
  • Lee has observed the importance of news media coverage.

In general, the present perfect seems to be more popular than the simple past, but note that when time-specific details are provided, the simple past may be required, as in:

  • In 1982, Lee observed the importance of news media coverage in a study that described the effects of TV-watching on adolescent development.

However, you could also write:

  • Lee has observed the importance of news media coverage in a study that describes the effects of TV-watching on adolescent development.

And if Lee has conducted further studies on the same topic, you might write:

  • Since 1982, Lee has observed the importance of news media coverage in several studies on the effects of TV-watching on adolescent development.

Forming Possessives

Possessives are used to indicate ownership. The possessive forms of nouns indicate that something (the second of two nouns) belongs to (is possessed by) the noun in question.

For singular nouns (e.g. dog, girl, book) possessives are formed by adding an apostrophe and then an “s”, as in:

  • The dog’s owner was away on vacation.
  • We don’t know the girl’s name.
  • The book’s chapters are all very interesting.

The possessive forms of plural nouns are formed in one of two ways. When the plural of the noun in question ends in “s” (e.g. dogs, girls, books), possessives are formed by adding an apostrophe after the “s”. No additional “s” is necessary. For example:

  • The dogs’ owners were away on vacation.
  • We don’t know the girls’ names.
  • The books’ covers were difficult to tell apart.

When the plural of the noun in question does not end in “s” (e.g. children, women, people), possessives are formed by adding an apostrophe and then an “s”. For example:

  • The children’s department features a variety of styles.
  • Susan enrolled in the Women’s Studies Department.
  • People’s thoughts are often not aligned with their actions.

When more than one noun possesses the same item (e.g. two people own a car together), only the second noun takes the possessive form, as in:

  • The point of Ackerman and Tolson’s study was to highlight deficiencies in the literature.
  • Jared and Claire’s dog looks like a mixed breed.
  • I think Sue and Jim’s car would look better in blue.

However, when two or more nouns have possession of different forms of the same item, all nouns take the possessive, as in:

  • The women’s, men’s, and children’s departments are on different floors.
  • Sarah’s and Tiffany’s grades are vastly different.

Note that possessive adjectives (e.g. yours, ours, theirs, hers) need no apostrophe:

  • This is yours?
  • Ours were excellent seats.
  • I thought it was theirs, but I wanted to be sure.
  • When you bring hers, please also bring mine.