In every language, there is a grammatical rule that is so embedded into the language that its native speakers are barely aware of it, even as non-native students of the language struggle to master it.
When I studied abroad in the Soviet Union,1Younger readers, ask your parents; it was a country more or less where Russia is now. I remember having a conversation with some Russian friends about the challenges of learning each other’s languages. “What’s the hardest thing about Russian grammar?” one of my friends asked me. “Oh, that’s easy,” I answered. “Verbs of motion.” (I even said this in Russian.)
“Verbs of what?” came my friend’s confused reply. He had never even heard of this category of verb—a category that bedevils students of Russian to this day. I explained what I was talking about, but it was clear that he was still mystified.
“Your turn,” I said. “What’s the hardest thing about English?”
“Sequence of tenses,” he said. In English.
“Sequence of what?” I replied.
A Deep-Seated Rule
The rule about the sequence of tenses in English grammar is one of those rules of syntax that is so deeply embedded that rarely is it even taught—it’s just something that every native speaker knows.
The rule is this: in a supbordinate clause (such as with reported speech), the tense of the verb of the subordinate clause is adjusted to match that of the main clause. Let me give you a couple of examples:
Lisa said that she was going to the movies.
Joaquin said that he had read a lot of books.
Renata said that she would go to Europe next summer.
In each of the examples above, the verb of the direct speech is shifted in tense when it becomes reported text: the present progressive becomes the past progressive, the present perfect becomes the past perfect, and the future becomes the past (would is the past tense of will).
This rule doesn’t apply only to reported speech; it applies to all such subordinate clauses;
I knew the Washington football team was going to lose.
Kwame believed that Amira would be an excellent president.
In many other languages, the tense would stay the same as it had been in the original statement. For example, in Russian, it would be grammatical to say, “Lisa said that she is going to the movies,” “Renata said that she will go to Europe next summer,” and “Kwame believed that Amira will be an excellent president.”
But that’s not how English does it.
A Question of Style (Again)
Now, some of you—again, likely the younger readers—may be saying, “But you can say things like that in English.” And that’s partially true. There is evidence that the sequence of tenses rule is fading in English, particularly among younger speakers. And so, you may have said sentences very much like those that my Russian friend would have found unremarkable.
There is even an exception when the condition described is permanent and would remain true in the present tense regardless. For example, the past tense of I learn that the sky is blue can be rendered either as I learned that the sky was blue or I learned that the sky is blue.
However, it’s important to note that this is still a rule of formal, written English. However you might say things in ordinary conversation, standard English style requires the use of a sequence of tenses.
It can be easy to get this rule wrong because we often begin a sentence in one tense, and by the time we’ve gotten to the end, we’ve forgotten what tense we were in and shifted to another one. That’s why it’s so important to be aware of this rule and to pay attention to it when we’re reviewing our written work.
Will our writing still be comprehensible if we don’t follow this rule? Probably, but it might seem a little “off” to a reader to encounter a sentence like Kwame knew that she will be an excellent president. To most English speakers and readers, a sentence like that will feel not quite right—especially if it turned out that Amira lost her election.
The rule on the sequence of tenses is one of those rules that most native English speakers don’t even realize exists. Nevertheless, careful writers will want to be able to say that they knew this rule and understood how important it was to good English style.