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Grammar

Relative Clauses: Extra Information (2)

Using preposition + whom/which, quantifiers like all of whom/which, and which to refer to a whole clause

Preposition + whom / which

In formal English, you can place a preposition directly before whom (for people) or which (for things) in a non-defining relative clause.

PatternExample
to whomThe hiring manager, to whom I sent my CV, called me back the same day.
with whichWe use a project tool, without which the team would miss every deadline.
of whomThe CEO, of whom you may have heard, is joining the call.

In everyday spoken English, the preposition usually moves to the end of the clause, and whom becomes who:

  • The hiring manager, who I sent my CV to, called me back the same day.
  • We use a project tool, which the team can’t function without.

Do not use whom when the preposition sits at the end. Say who I sent my CV to, not whom I sent my CV to.

Quantifier + of whom / of which

You can combine a quantifier with of whom (people) or of which (things) to add extra information about part of a group.

QuantifierPeopleThings
all / most / many / some / noneall of whom, most of whom, etc.all of which, most of which, etc.
both / neither / one / two / halfboth of whom, neither of whom, etc.both of which, neither of which, etc.

Examples:

  • We interviewed twelve candidates, most of whom had strong project management experience.
  • The board raised several objections, none of which were difficult to address.
  • I manage two interns, both of whom started last month.
  • The company owns four warehouses, one of which is located overseas.

You can also use the + noun + of which to refer to a characteristic of something:

  • We signed a five-year contract, the terms of which are still confidential.
  • The server went down due to an error, the cause of which is still under investigation.

Which Referring to a Whole Clause

Which can refer back to an entire fact or situation, not just a single noun. In this pattern, which means “the fact that …” or “this thing.”

  • The client approved the budget on the first try, which surprised the whole team. (which = the fact that the client approved it so quickly)
  • Our office will be closed next Friday, which means we need to finish everything by Thursday.
  • David forgot to mute his microphone, which was pretty embarrassing.

Use which here, not what:

CorrectIncorrect
The deadline was moved up, which nobody expected.The deadline was moved up, what nobody expected.
She got promoted, which made her very happy.She got promoted, what made her very happy.

Quick Self-Check

Question 1

The regional director, _____ I reported directly, approved my transfer request.

Select your answer:

Question 2

We interviewed six applicants, none of _____ had the required certification.

Select your answer:

Question 3

The company launched three products last year, two of _____ were discontinued within six months.

Select your answer:

Question 4

The meeting was cancelled, _____ meant we had the whole afternoon free.

Select your answer:

Question 5

We signed a new vendor agreement, the terms of _____ will take effect next quarter.

Select your answer:

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