This subject was brought to my attention by Mohan Angbo from Nepal who’s been asking me some great questions.
He asked why we need that in some sentences but not in others. I suspect that many of you will find this an interesting subject.
Well, at least some.
Let’s start by looking at two example sentences. We want to know why you can take out the connecting “that” in the first sentence and not in the second sentence.
Have a think with me. Do you know the answer?
1 He said [that] he would come.
I can also say or write:
He said he would come.
This is a correct sentence too.
2 We heard the news that he would come.
I cannot say or write:
We heard the news he would come.
What’s the Difference Between the Two Sentences?
On first sight, both sentences seem to be similar.
Both are sentences that consist of two simple sentences, that are put together.
Sentence one is made up of two sentences:
A He said.
B He would come.
Sentence two contains two sentences too:
1 We heard the news.
2 He would come.
Okay, so this hasn’t taught us anything, has it?
Well, that is because there is another difference between the two sentences.
In sentence one, I have two subjects in each sentence (clause): he.
It’s clear that he is doing something in he said, and also in he would come.
So then I don’t need that.
In sentence two, that doesn’t refer to the subject, but to the object (the news). For more information about objects, have a look here.
The he in the second clause is not a person who is doing something, but he is part of the object clause. What is the news? The news is that he would come. So he would come is not a separate action.
So now we can formulate a rule:
You can leave that out when it connects two independent clauses (sentences) that each have a separate subject that does something.
If there is not a separate subject that does something in the second clause, you can’t leave that out.
Let’s investigate some more examples:
3 We went to the restaurant that Sally recommended to us.
Can I leave that out?
At first sight this looks like sentence 2 (We heard the news that he would come), but it’s not the same. Sally recommended to us is clearly an example of an active sentence and not some add-on to an object. Sally recommended the restaurant to us. So Sally is an active subject. You can leave that out.
This is okay too:
We went to the restaurant Sally recommended to us.
Here are some more examples:
4 The manager showed her plans to the executives that were seated in front of her.
Can I take that out?
Nope.
The second clause (that were seated in front of her) doesn’t have a subject. The subject of this clause is in the first clause (the executives), but not in the second clause.
Our little rule is still valid. The second clause has no active subject, so we can’t leave that out.
5 The couple that we met yesterday have no children.
We can leave that out, because the second clause has a separate active subject (we).
6 The couple that is in the picture have no children.
We can’t leave that out, because “is in the picture” doesn’t have a subject.
(We can however say: The couple in the picture have no children. Without is.)
For this kind of ellipsis you can check out this article.
7 We saw the couple that have no children.
I can’t take out that because “that have no children” has no subject.
Another Reason Not to Take Out That
You can’t omit that when there is an adverb or adverbial phrase between the first sentence (clause) and that, and when this adverbial thing makes the sentence incomprehensible without the that.
An adverb or adverbial phrase is a word or words that indicate time, place or manner.
What do I mean?
Check out this example first of all:
8 We saw the couple afterwards that have no children.
Here we need that because afterwards is in the middle of our sentence. We need that again as a reminder that we were talking about the couple.
So I can’t say: We saw the couple afterwards have no children.
Sounds bad, right?
Also the meaning of the sentence has changed now. It sounds as if we were looking at the couple and while we knew them no children were born to them. Weird!
Another example:
9 Merrill learnt a trick from a magician in Brooklyn that she had admired for a long time.
Can we leave out that?
Well, I don’t know. It has “in Brooklyn” as an adverbial phrases before that. Let’s see what happens when we omit that:
Merrill learnt a trick from a magician in Brooklyn she had admired for a long time.
It’s clearer with that, don’t you think?
And last example:
10 There isn’t much at all that he doesn’t notice.
Can we leave out that?
No, not a good idea, because there is “at all” between the thing that that refers to and the second clause.
There isn’t much at all he doesn’t notice: this sentence is not very clear. Some readers will get confused because they will think that all is the subject of the relative clause. The sentence is better with that.
Okay, you’ve probably more or less got it now.
Just one more note before we (you) tackle the quiz.
Why is this Subject So Difficult?
In case you were wondering whether this subject was impossibly difficult, yes, you’re right. Even I think this is pretty difficult, to explain it right. I’m sure most native speakers will not ever in their lives think about why they use that in some cases and not in other cases, let alone know a rule for it. This subject is done purely on intuition. In fact I haven’t found a good discussion in any of my grammar books (I’ll throw them away tomorrow).
So now you can do a quiz, but don’t worry too much if you have some mistakes in this. When you use English a lot, you will probably get this right automatically, because you’ll develop your own English intuition.
What Kind of Clause?
Another note for grammar lovers who appreciate using the exact professional jargon: in this article I’ve talked about that in defining relative clauses, so not with commas (,). We’ll talk about non-defining clauses some other time, but they’re actually easier. So that’s good.
Warning: The quiz is super advanced! Not for beginners at all.
Quiz
Click here to do the quiz online.
Decide whether that can be left out in the following sentences.
1 I told you that the baby couldn’t be left alone even for two minutes.
2 Look at the mess that your son has made in our living room.
3 It’s clear that you will have to clean the sofa.
4 And look at the drawings in that corner over there that he’s made with finger paint.
5 If we’d have a proper babysitter that wouldn’t have happened.
6 Yeah, you’ve told me before that we don’t have money.
7 Oh my gosh, have you seen that he’s cut the fringes off the carpet?
8 Don’t tell me that he’s only a small child.
9 He’s a small child that can cut like an adult.
10 Let this be your lesson that our baby should be watched.
Want to do other quizzes about sentence formation? I recommend reading this article: