I totally agree to your explanations, but as you mentioned 'which' is a general (non defining) clause that can be omitted without weakening the sentence (the same with a non defining clause, i.e 'The mount Everest(, that is covered with snow,) is the highest mountain in the world.')
Shovelling snow is something (which I do not prefer).
without the defining clause does the sentence not make any sense, therefore the correct sentence is
Shovelling snow is something that I do not prefer.
by the way, you can bet that in any SC in which you have a 'which' without a comma, there is something else wrong in the sentence! cheers
i also found some followup information.
That vs. Which
1. GMAT almost always wants you to put a comma before which
. In other words, if you see which without a comma before it, it's probably wrong.
If the person you're talking to, or the person who's reading what you've written, needs that extra bit of information to know which noun you're referring to, we say that that extra information is non-restr
On the other hand, if you need that information to know which noun you are talking about, we say that the information is restrictive
. Again, this word is not really a good choice for clarity, and many teachers use the term "necessary information" instead
We need a comma before non-restrictive clauses and phrases but it is not needed before restrictive clauses and phrases.
Both the sentences below are correct according to GMAT, but have different meanings.
· Please go into the room and get me the big book, which
is mine. (Ex: of non-restrictive)
· Please go into the room and get me the big book that
is mine. (Ex: of restrictive)