Writing in Science: Practical Tips Academic Writing Science Communication
Practical Tips: That vs Which



article use

British vs American


compare to/with


dates & numbers

dangling participle

eponymic terms


-ic vs –ical



like vs such as



faulty parallelism

passive voice


sentence structure


spell check
split infinitives


that vs which

unusual plurals


word confusion

Michael Quinion on World Wide Words writes: that-which ppt

“Older grammar books make two firm points about the difference between the two types of clause:

  1. Restrictive clauses are introduced by that and are not separated from the rest of the sentence by commas.
  2. Non-restrictive clauses are introduced by which and must be separated by commas from the rest of the sentence to indicate parenthesis.

One key proviso: you can use which instead of that in restrictive clauses, you cannot do so the other way round: non-restrictive clauses should always to start with which.

A further point worth noting is that the opening pronoun in non-restrictive clauses is frequently left out, so that you can say “The cup (which) he stepped on is in the bin”. .

Thus, you can check whether you have a restrictive or non-restrictive clause by trying to leave it out of the sentence: if the sentence does not change meaning, the clause was non-restrictive.

Which is correct?

“To our knowledge, it is the only body in the solar system which currently sustains life, although several other bodies are under investigation.”

“To our knowledge, it is the only body in the solar system that currently sustains life, although several other bodies are under investigation.”

ANSWER: the second one

Note the different nuances of meaning:

The painting that was hanging in the foyer was stolen.

It was the foyer painting that was stolen, not the kitchen or living room ones.

The painting, which was hanging in the foyer, was stolen.

The painting being the one we were discussing.

The Van Gogh that was hanging in the foyer, which we purchased in 1929 for $10 000, was stolen.


DailyWritingTips. [Internet accessed 30.05.2011] Available from: http://www.dailywritingtips.com/that-vs-which/ Grammar Girl. Which versus that. [Internet accessed 30.05.2011] Grammar: Quick and Dirty Tips. Available from: http://grammar.quickanddirtytips.com/which-versus-that

Lawler J. That vs. which [Internet accessed 30.05.2011] English Grammar FAQ. University of Michigan. Available from: http://www-personal.umich.edu/~jlawler/aue/xmasthat.html

Lynch J. Guide to Grammar and Style. [Internet accessed 30.05.2011] Rutgers University. Available from: http://ethnicity.rutgers.edu/~jlynch/Writing/t.html

Quinion M. Which Versus That: When to use each in subordinate clauses. [Internet accessed 30.05.2011] World Wide Words © 1996–2011. Available from: http://www.worldwidewords.org/articles/which.htm

Sevastopoulos J. Clauses. [Internet accessed 30.05.2011] Grammar Quizes. Palo Alto, California USA. Available from: http://www.grammar-quizzes.com/clauses-5.html

That Versus Which. [Internet accessed 30.05.2011] Illinois Institute of Technology. Chicago-Kent College of Law. Available from: http://www.kentlaw.edu/academics/lrw/grinker/LwtaThat_Versus_Which.htm

Questions? Suggestions? contact: elinor.bartle<at>uib.no