© 2009-2011 Ugur Akinci
Sometimes we all would hesitate whether to use “that” or “which” in a sentence.
This would not be a problem only if they were truly interchangeable.
But actually they are not.
They stress different things as was first formulated by Rev. Edwin A. Abbott in his 1883 classic “How To Write Things Clearly.”
WHICH stresses the SUBJECT and VERB of the sentence.
THAT qualifies and explains its OBJECT.
“He closed down his business which did not make any sense.” (The act of closing down did not make any sense.)
Compare this to:
“He closed down his business that did not make any sense.” (His business – the OBJECT – did not make any sense.)
“She won a race which we knew nothing about.” (We did not know anything about her act of winning a race.)
“She won a race that we knew nothing about.” (We did not know anything about the race – the OBJECT – that she won.)
Eliminate ambiguity by selecting your words carefully.