Grammar and Comprehension: Scaffolding Student Interpretation of Complex Sentences

  • 10 December, 2013

Teacher question:

I'm a fourth grade special education teacher in NYC. Our school has acquired a new reading/writing program and has discontinued a grammar program we've used for several years. In the new program the grammar component is virtually non-existent. On a gut level I feel that students are struggling with test questions, even math ones, due to lack of practice/knowledge of grammar. They simply don't understand what the questions are asking. I was wondering what your opinion/research shows as far as the relationship between grammar instruction and reading comprehension. Do you have any preference as far as grammar programs/teaching methodologies go?  

Shanahan response: 

Great question. There is a lot of evidence showing the importance of grammar in reading comprehension. Studies over the years have shown a clear relationship between syntactic or grammatical sophistication and reading comprehension; that is, as students learn to employ more complex sentences in their oral and written language, their ability to make sense of what they read increases, too.

  Also, readability measures are able to predict how well students will comprehend particular texts on the basis of only two variables: vocabulary sophistication and grammatical complexity. At least for the Lexile formula, grammar is much more heavily weighted than vocabulary. This means that the text factor that is most predictive of comprehensibility is how complicated the sentences are grammatically.

  There are also experimental studies that show that there are ways that grammar can be taught formally that improve reading comprehension. For example, teaching students to combine sentences seems to improve how well students understand what they read. Clearly, it makes sense to guide students to understand how sentences work.

  Studies of metacognition and theories of reading comprehension suggest the importance of students having a language of grammar (knowing the difference between a noun and a verb for example), and common sense would suggest that it makes sense to help students to unpack sentences that confuse them.

  That doesn’t necessarily justify a lot of grammar worksheets and the like, but it does argue for teaching students about sentences as they meet them. For example, look at the following sentence from Nikki Giovanni:

  “The women of Montgomery, both young and older, would come in with their fancy holiday dresses that needed adjustments or their Sunday suits and blouses that needed just a touch—a flower or some velvet trimming or something to make the ladies look festive.”

  It is a long sentence (44 words), and it has lots of embedding (witness the author’s use of 2 commas and an em-dash). I surmise many students would struggle to make sense of this sentence primarily because of the complex grammar. How would you deal with this?

  First, I would have the students read this page from Giovanni’s Rosa and one of the questions I would ask would be, “What did the women of Montgomery do?” Perhaps I’d find that the students weren’t as perplexed as I assumed in which case I’d move on. But let’s imagine that they couldn’t answer my question... then I’d show them how to break this sentence down.

  For example, I would point out that the phrase between the commas, “both young and older,” adds an idea but that I want to set it aside for now. That would simplify the sentence a bit:

  “The women of Montgomery would come in with their fancy holiday dresses that needed adjustments or their Sunday suits and blouses that needed just a touch – a flower or some velvet trimming or something to make the ladies look festive.”

  Even with such a simple change, I bet more kids would understand it better, but maybe not. Let’s go further:

  As with the commas, the word “that” (which shows up twice here) signals the inclusion of a separate or additional idea, and as a reader that is another point of attack that I can use in trying to interpret this sentence. And the word “or” is another good place to separate these additional ideas.

  Let’s slice the sentence at the first “that” and the first “or:”

  “The women of Montgomery would come in with their fancy holiday dresses”

  “that needed adjustments”   

  "or their Sunday suits and blouses that needed just a touch–a flower or some velvet trimming or something to make the ladies look festive."

  Obviously, we could keep breaking this one down, but again, many kids would get it at this point: The women were bringing in their fancy dresses… Which women? The young and the old. Which fancy dresses? The ones that needed adjustments. What other kinds of outfits did they bring in? Sunday suits and blouses. Which suits and blouses? The ones that needed just a touch—something that would make them look festive.

  The point of this kind of exchange would not be to teach grammar per se, but to help students to untangle complex grammar so that they could independently make sense of what they read. Frankly, few of our children know what to do when they confront this kind of text complexity. Kids who know something about sentences and parts of speech will be at an advantage, but they still will not necessarily be able to interpret a sentence from that alone. This kind of scaffolded analysis is aimed at both untangling the meaning of this sentence and in giving students some tools for unpacking such sentences when they are on their own.

  Your reading program should provide some instruction in grammar, and it should provide you with some support in providing students with instruction in parts of speech, sentence combining, and/or the kinds of scaffolding demonstrated here. It is pure romanticism that assumes that children will just figure this kind of thing out without any explicit instruction (and it is even more foolish to assume that English language learners will intuit these things without more direct support).


See what others have to say about this topic.

Cynthia C Jun 19, 2017 10:02 PM

Just what I was looking for to synthesize the idea that understanding in basic grammar helps the learner to better comprehend. Thank you for the wonderful explanation.

Mr. Ryan Higbea Jun 19, 2017 10:02 PM


Thank you for this post. Can you provide citations for these studies and evidence you mention in the post? We're looking implementing a school-wide intervention that involves grammar instruction, but it must be research-based and I'm interested in reading the original research that shows a causal relationship between explicit grammar instruction and increases in reading comprehension.

Thank you! Ryan

Timothy Shanahan Jun 19, 2017 10:03 PM



There is no research showing that explicit grammar instruction improves reading comprehension or writing. The few studies there are on this topic have typically focused on grammar instruction as the control group, and it has been put up against various experimental treatments that have tended to do better than it (in other words, we could use a really good study where someone provides a high quality explicit grammar program aimed at improving comprehension--placing that up against usual practices).

However, there is a plethora of evidence on "sentence combining" and sentence-reducing and their role in reading and writing. Such instruction is not considered to be explicit, but it does guide students through exercises that show them how sentences work (by having kids break and build sentences). Here are a few of the many studies or summaries of research in this area.

Andrews R, Torgerson C, Beverton S, Freeman A, Locke T, Low G, Robinson A, Zhu D (2004) The effect of grammar teaching (sentence combining) in English on 5 to 16 year olds’ accuracy and quality in written composition: Review summary. University of York, UK.

Combs, W. E.. (1977). Sentence-Combining Practice Aids Reading Comprehension. Journal of Reading, 21(1), 18–24

Graham, S., & Perin, D. (2007). Writing next: Effective strategies to improve writing of adolescents
in middle and high schools – A report to Carnegie Corporation of New York. Washington, DC:Alliance for Excellent

Hillocks G Jr (1984) What works in teaching composition: a meta-analysis of experimental treatment studies. American Journal of Education 93: 133-170.

Mellon J (1969) Transformational Sentence Combining. Research Report No. 10. Urbana, IL, USA: National Council of Teachers of English.

Neville, D. D., & Searls, E. F. (1991). A meta?analytic review of the effect of sentence?combining on reading comprehension. Reading Research and Instruction, 31, 63-76.

O'Hare F (1973) Sentence Combining: Improving Student Writing without Formal Grammar Instruction. Research Report No 15. Urbana, IL, USA: National Council of Teachers of English.

Stotsky SL (1975) Sentence-combining as a curricular activity: its effect on written language development and reading comprehension. Research in the Teaching of English 9: 30-71.

Wilkinson, P. A., & Patty, D.. (1993). The Effects of Sentence Combining on the Reading Comprehension of Fourth Grade Students. Research in the Teaching of English, 27(1), 104–125.

Leslie Lim Jun 19, 2017 10:03 PM


I read your blog.I thought it was great.. Hope you have a great day. God bless.


Line Skat Henningsen Jun 19, 2017 10:04 PM


Thank you for this post. I really enjoyed reading it.

I live in Denmark and teach children in a municipal lower and primary school (special education)in Copenhagen. Besides teaching I am studying to become a reading tutor at my school. I totally agree that children need to learn grammar in a context which they can transfer to their own texts. As a teacher I have learned that isolated grammar exercises have no effect on pupils ability to transfer it (knowledge) to their own texts, despite the fact that they might get 100 % correct answers on their grammar exercises.
One part of the pupils final exam in the subject Danish is grammar questions e.g.. pupils have to conjugate verbs and show "grammatical attention" i.e. the have to find a word (e.g. noun) in a "word-jumble"

Now to my question:
Does it make sense that the exam in Danish spelling has isolated grammatical exercises when teaching should avoid working with grammar as/in isolated exercises?

Timothy Shanahan Jun 19, 2017 10:04 PM


I had always been told that research did not find grammar instruction to be effective at improving reading and writing with native speakers. However, I had accepted that without reading those studies. In none of the research was grammar instruction the experimental intervention, it was always the control group--which to me means someone might be able to come up with an isolated grammar program that would be effective. However, until that is done, I think it makes the best sense to use approaches like sentence combining or sentence reducing, since research on those have shown clear impacts on outcomes that we care about. I personally don't see any reason for an isolated grammar test... much more interested in either the students' ability to interpret grammatical relations to answer questions about a text or to use grammar well in a composition. However, if there is to be an isolated grammar test the question to ask is how closely correlated the measure is to reading comprehension and writing quality--if it is high enough that might be acceptable.


First Last Jun 19, 2017 10:05 PM


Why isn't there "research that shows a causal relationship between explicit grammar instruction and increases in reading comprehension?" I'm always pushing that link on the students I tutor. (They might not even need me were the link better accepted by schools.)

Timothy Shanahan Jun 19, 2017 10:05 PM


What I'm saying is that there is no study in which some students are taught grammar and an equivalent group is not that shows any impact on student reading comprehension or writing.

Ritah Aug 10, 2020 06:43 PM

I just can't wait to learn more from this program

Amy Christy-Davila Sep 12, 2020 11:53 PM

I am a beginning PhD student and am interested in looking at grammar for students with language-based learning disabilities (LBLDs). In particular, I have notice that the reading and writing difficulties of many of my former students with LBLDs are not restricted to problems with decoding and encoding. They have difficulty with sentence expansion in writing and with reading and comprehending complex sentences. There was a 1997 study that showed that explicit teaching of grammar may have a negative impact on writing progress.

I would be interested in finding out more about your thoughts on how I might go about setting up a study of the impact of explicit teaching of grammar as part of the reading and writing processes.

What Are your thoughts?

Leave me a comment and I would like to have a discussion with you!

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Grammar and Comprehension: Scaffolding Student Interpretation of Complex Sentences


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