Do Your Verbs Agree with Your Subjects?

© 2009-2010 Ugur Akinci
It’s a fundamental rule of English grammar: your VERB must agree with the SUBJECT of your sentence.
Why I’m addressing this very basic rule?
The reason is, when violated, it can have disastrous consequences in technical writing.
First the RULE:
The garage [Main SUBJECT] where he kept [auxiliary VERB] his antique car is [Main VERB] very old.
(Garage … is)
VIOLATION of the rule:
The garage where he kept his antique cars are very old.
(Garage … are?)
MS Word actually flags such violations by underlining the offending verb with a squiggly green line is the “Check grammar with spelling” check box is selected in the Options configuration window (Tools > Options).
So why that kind of violation can have bad consequences in technical documentation?
Here is why:
Imagine you’re writing the Security Procedures Handbook for a secure military facility. Your main goal as a technical writer is to make sure there are no mistakes in your document that would allow the bad guys infiltrate the facility or inadvertently cause one of the good guys get injured.
Imagine you write a procedure like the following:

When the Red Light starts to flash, make sure one the following gates are closed and locked within 2 seconds:
– Gate A at the North Sector
– Gate B at the South Sector
– Gate C at the East Sector

Of course the correct sentence should read “…one the following gates IS closed…”
If your reader is reading the sentence carefully, it’s clear that only ONE of the gates should be closed.
But if the reader is concentrating on the verb ARE, he or she can easily think that ALL the gates should be closed, especially in a panic situation.
If the Red Light is a fire alert, for example, you may cause people getting trapped and burned unnecessarily if the operator shuts down all the gates by mistake.
You can never guess in advance the kind of “unintended consequences” such a seemingly-simple grammatical error might cause.
So watch your grammar and write clean procedures that have no room for any misunderstandings.
To your precise success!