Subject-verb agreement is about the changes that occur in the spelling and pronunciation of present tense verbs and the past tense as well as the present tense of be under the influence of certain kinds of nouns and pronouns. 
 

The SVA rule is one that seems to puzzle many ESL/EFL teachers.  The rule seems so simple, but students don't get it--they don't apply it consistently and accurately until quite advanced levels of proficiency.  SVA is a central example of a grammar topic that is (fairly) easy to teach and (extremely) difficult to learn.

SVA is complicated.  That basic rule is really deceptive because so much underlying knowledge is required to carry it out.  What does a student have to know about sentences to be able to do SVA accurately?  Try making a list of the underlying grammar.  Then click here to see my list.  Please let me know about other things that I should add to make my list more complete.

Sometimes SVA seems to be approached as a "mystery" in discussions of second language acquisition.  Why does it take so long?  What's going on the socio-psycho-makeup of learners that takes so long?  Well, it's a complicated thing to learn to do.  It just looks easy on the surface!

Another complexity in SVA is that English has only two ways to present present tense verbs--it's either without the -s or with the -s.  So, that's a system with 2 parts.  But we have a noun system with three sub-categories: singular count, plural count, and noncount.  Singular count goes with verb+s.  Plural count goes with the unchanged verb.  That leaves the noncount with no form to use.  So, we have to assign noncount to one of the other categories to get a verb to go with it.

This mismatch lies behind a useful rule of thumb: if a noun isn't clearly plural, it is treated as if it were singular.  That generalization helps us to understand why noun replacement forms such as infinitives take the singular verb.  Notice that all of the non-noun subjects in the following list take the -s or "singular" verb form.
 
 

I'm not going to go through all of the special cases that add complexity to the basic rule.  These are well documented in other sources.  These complexities include topics like the use of nouns that look like plurals but that aren't.  A common one of these that often trips up our ESL/EFL learners is the word news.  It looks plural; news does involves more than one thing.  But, of course, it's really noncount and treated like a singular for SVA purposes.
 
 

Unlike other topics that we've considered from a discourse point of view, SVA is not (and cannot be) limited to occuring in a particular type of communication.  Do you see the logic of that statement?  SVA is a process that occurs with all subjects and present tense verbs; it could only be missing from a discourse type that used only past tense (but be would complicate that discourse type with its past tense SVA).   

In that case, what can we learn from corpus linguistics?   Three things come to mind.  

First, we can find out if the complicated noun types are used very much--perhaps find a rank ordering that would help us decide which complexities to spend time on with our students.  

Second, we can find authentic examples that we can use with our students or can use as models for examples on topics more of interest to our students.

Third, we can re-think the SVA topic into a verb tense topic:  Where are simple present tense verbs used a lot?  Is that different from discourse that uses present perfect a lot or present progressive a lot? If so, then, we could put the presentation and practice of SVA into those contexts.  That is, if simple present tense is used a lot in conversation, we can work on SVA by working on conversational strategies.  If simple present tense is used a lot in making generalization (and rule statements in academic prose), then we can use that context.

How do we take this information and use it as ESL/EFL teachers?  How do we go about helping our students learn to do something both basic to the nature of English and very complicated to learn to do?

Please email me your questions and comments.   Thanks.

        Biber, D., Johansson, S., Leech, G., Conrad, S., & Finegan, E. (1999). Longman Grammar of spoken and written English. Edinburgh Gate, Harlow, England: Pearson Education Limited.

        Celce-Murcia, M. & Larsen-Freeman, D. (1999). The grammar book: An ESL/EFL teacher's course.  (2nd ed.)  Boston: Heinle & Heinle.