Subject–Verb Agreement

Recently, I was asked to review a book for which the author supplied a press release. It included this sentence (I’ve adapted it to keep it anonymous):

‘As a retired counsellor, I know that relationships between one human being and another is a critical human learning we must master.’

A mistake like this is surprisingly common. When I come across it, it makes me think twice about reading the book (especially when the press release has many other errors as well). In this case it was disappointing, as the book sounded interesting. Instead of leaving me feeling enthusiastic, this press release made me feel suspicious and prepared for the worst. That’s not how it should be!

Of course, the sentence should have read:

‘As a retired counsellor, I know that relationships between one human being and another are a critical human learning we must master.’

In other words, the verb must agree with the intended number of the subject. What does this mean? It means you must:

1       identify the real subject of the sentence;

2      work out whether the subject is singular or plural.

In this example, the real subject of the sentence is relationships and it is in the plural (relationships not relationship). So we must refer to them in the plural: ‘are’ not ‘is’.

This sounds straightforward, but several things can complicate the issue, especially when sentences are long and complex. Practice makes perfect!

It’s also a common mistake to write a singular verb after a list where the last item on the list is a singular noun:

• His socks, shoes, trousers, and jacket is always impeccable. ✗

Or a plural verb instead of a singular:

• Susie had invited a list of guests that were impressive. ✗

Remember, also, that collective nouns (e.g. group, herd, flock) take a singular verb because they themselves are singular: ‘The herd is very large’ (there is only one herd, so we use ‘is’ not ‘are’).

The same goes for each, everyone and everybody, which always take a singular verb:

•       ‘Each of us has a packed lunch and a bottle of water.’

•       ‘Everyone has travelled here by bike.’

•       ‘Is everybody happy?’

None, on the other hand, can be either singular or plural depending on whether it is read as ‘not one’ or ‘not any’. Both of the following are acceptable:

•       ‘None of my brothers likes broccoli.’

•       ‘None of my brothers like broccoli.’

When none is clearly intended to mean ‘not one’, however, it is followed by a singular verb:

•        ‘None of the delegates was prepared to take a stand.’

Summary

In a complicated sentence, take time to work out what is the subject of the sentence and whether it is plural or singular.

Look at your use of is and are. Is it correct?

If you need practice, look back at this section and try to find your own examples.

Final Summary

Getting these tips right will help lift your work above the majority of independently produced books. As you have seen, it’s not hard to do and it doesn’t actually involve a great deal of work. All it needs is careful thought and good organization.

Remember: don’t trust your memory! That is the way professional copyeditors work.