Focusing on Word Structure

As we were watching a video about the water cycle, I wrote the following words on the board:

condensation                  evaporation                         transpiration
infiltration                       percolation                          precipitation
interception                     evapotranspiration

What an orthographic opportunity!  The students were quick to recognize that everyone of these had an <ion> suffix.  Next I asked students to say and then spell the word that would remain if the <ion> suffix was removed.  The words listed were now:

condensate                     evaporate                            transpirate

infiltrate                         percolate                              precipitate

intercept                        evapotranspirate

With the exception of the word <intercept>, all the rest had something in common.  The students again pointed out an <ate> suffix.  I asked why the <e> on the end of <ate> didn’t show up once we added the <ion> suffix to the word?  Everyone knew that it was dropped when the vowel suffix <ion> was added.  At this point I recognized though, that some of the students thought the second suffix was <at> instead of <ate>.   In our recent “The Great Suffix Challenge” activity I learned that some of those same students have little understanding of suffixes, other than their position in the word.  We must keep writing out word sums and talking about each morpheme’s role in the word.

Next I asked if anyone recognized any proven prefixes.  Several recognized <inter>, meaning between and <pre>, meaning before.  Even though we had previously discussed <e> being a clip of <ex> (meaning out) and <con> (meaning together), no one recognized them offhand.    I grouped the students and had each group further investigate each word.

As the bases were identified, discussions took us in all sorts of fascinating directions.

The meaning of the word <evaporation> became something we could clearly picture once we knew that <e> was the prefix meaning out  and <vape> was the base meaning steam.  We pictured water evaporating from a tea kettle, a puddle, and a lake.  Our complete word sum hypothesis was <e> + <vape/> + <or> + <ate/> + <ion>.   When deciding whether the base was <vape> or <vapor>, we looked for other words sharing this meaning and found <vapid>.  This word was our evidence that <or> was a suffix.  We decided that without the final <e> on the base, the final consonant <p> would be forced to double when adding a vowel suffix.  Since we know that in words like vaporize and evaporate there is only a single <p>, then we also know there must be a final <e> on the base <vape>.  For those who were confused as to why the base might have a final <e>, I wrote <hoping> on the board and asked them to remove the <ing> suffix.  When they said the base was <hope>, I showed them that the final <e> in <hope> is doing the same job as the final <e> in the bound base <vape>.

Another intriguing discussion arose with the word <infiltration>.  The word sum hypothesis was <in> + <filtr> + <ate/> + <ion>.  As we typically do, we looked for other words that shared the base <filtr> and its meaning.  We found filtration, infiltrate, infiltrator, infiltrated, filter, filtering, filtered, and filters.  Much to my delight, someone asked how we could add an <er> suffix to the base <filtr> to get the word <filter>.  The student knew we wouldn’t just drop the final <r> in the base, but also knew that simply adding the <er> suffix wouldn’t get us the spelling of <filter> either.

The bound base <filtr> behaves similarly to <centr>, <metr>, and <theatr>.  Structurally it makes sense to spell these four with a final <re> rather than an <er>.  Let me give examples using word sums:

<filtr> + <ate/> + <ion> –> <filtration>
<centr> + <al> –> <central>     OR     <centr> + <i> + <fuge/> + <al>  –>  <centrifugal>
<metr> + <ic> –> <metric>       OR    <metr> + <o> + <nome>  –>  <metronome>
<theatr> + <ic> + <al>  –> <theatrical>

In other countries, these words are indeed spelled <filtre>, <centre>, <metre>, and <theatre>.  At some point in American history, the <re> ending was reversed so that these words resembled all of the other words in our language that have an <er> suffix.   Alas! In doing so, another road block to understanding word structure was set in place.  Center and central seemed to be two words that were related in meaning, but not in spelling or structure.  But, of course, that is not what scholarly research and evidence reveals!  My students are now as fascinated with this information as I am.

One final treasure was when we found the base of <transpiration> to be <spire> which means to breathe.  The students began collecting other words with that base and we talked about how each word shared that sense of breathing.  When we studied photosynthesis, we first used the word <transpiration>, and knew that it was that plant action of pulling water up from the roots, through the xylem, through the leaf into the cell and out the stomata.  In this way the plant is breathing.  When we came across the word <perspiration>, the light bulb of meaning connection went off in my own head and I said, “Transpiration.  Perspiration.  Anybody seeing any similarities in meaning?”  Eyes widened and hands shot up.   From there we talked about <respiration>, <inspiration> and <expiration>.  THIS is the stuff you don’t find in spelling workbooks!