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7.6  Problems
Appendices

7.6 

Problems

This problem concerns Lingala verbs. Each of the verbs in the lists below has three morphemes: a root; a morpheme indicating the person and number of the subject ('I', 'you:SINGULAR', 'he/she', 'we', 'you:PLURAL'); and a morpheme indicating some aspect of the time, the likelihood, or the desirability of the state or event. I'll refer to these three categories of morphemes as root, subject, and tense-aspect-modality (TAM). The following values of TAM appear in the lists below (you don't need to bother with what they actually mean): SIMPLE PRESENT (SIMP PRES) PRESENT PERFECT (PRES PERF), FUTURE (FUT), SUBJUNCTIVE (SUBJ).

Tone, marked by the presence (high tone) or absence (low tone) of an accent mark on vowels, is important in the lexicon and the grammar of this language; don't ignore it! To write accent marks, you can put them after the vowels. Don't type accented characters in your word processing program, then save them as text and upload them to Annotate; they won't show up in Annotate. If you want accented characters to display in Annotate, you have to use the HTML codes for the characters. If you know these, feel free to use them.

In the first list of verbs, all are in the SIMPLE PRESENT form. You just need to figure out what the subject morphemes are and where they come in the words.

Word Root Subject TAM
nakoma write I SIMP PRES
tokoma write we SIMP PRES
tokóma arrive we SIMP PRES
okóma arrive you:SING SIMP PRES
osómba buy you:SING SIMP PRES
asómba buy he/she SIMP PRES
akabola divide he/she SIMP PRES
bokabola divide you:PLUR SIMP PRES
bondima agree you:PLUR SIMP PRES
tondima agree we SIMP PRES
osepela enjoy you:SING SIMP PRES
asepela enjoy he/she SIMP PRES
natatabana be:surprised I SIMP PRES
botatabana be:surprised you:PLUR SIMP PRES
toloba speak we SIMP PRES
nabóngola change I SIMP PRES
oyébisa tell you:SING SIMP PRES
atámbwisa drive he/she SIMP PRES
botúna ask you:PLUR SIMP PRES
napangwisa wipe I SIMP PRES
atála look he/she SIMP PRES
obóndela plead you:SING SIMP PRES
  1. Where in the words does the subject morpheme appear?
  2. What are the morphemes for the following subjects?
    1. 'I'
    2. 'you:SINGULAR'
    3. 'he/she'
    4. 'we'
    5. 'you:PLURAL'

I'll describe informally the process of how you might solve the problem.

Start by looking for some pairs whose meanings differ by only one morpheme. The first two words nakomo and tokoma differ only in that one has 'I' as subject, the other 'we'. The difference between the two forms is that the first begins with na, but the second begins with to. So tentatively at least we can assume the following:

  • na- 'I'
  • to- 'we'

Both of these morphemes come at the beginning of the word. Since morphemes belonging to the same set usually appear in the same place in the word, we can guess that the other subject morphemes will also appear at the beginning.

Before we go on, we might check to see if we are right so far by looking for other words with subject 'I' or 'we'. In fact all of the with subject 'I' begin with na, and all of those with subject 'we' begin with to.

Now we can either continue to look for pairs differing by only one morpheme, or we can try a different approach and look for all of the words containing a given unknown morpheme and see what they have in common. Let's try this second way and look for the morpheme meaning 'he/she'. The words containing that morpheme are asómba, akabola, asepela, atámbwisa, atála. These all share two things: they all begin with a, and they all end with a. But the a at the end could have nothing to do with 'he/she' because it is at the end of all of the words in the list (so probably has something to do with what all of the words share, that is, SIMP PRES). Based on what we already know, it is the beginning where we expect the subject morpheme to appear, so we can know conclude the following:

  • a- 'he/she'

That leaves two more subject morphemes, 'you:SING' and 'you:PLUR'. We can do the same thing we did for 'he/she' and look for all of the words that share these morphemes. For 'you:SING' they are okóma, osómba, osepela, oyébisa, obóndela. These all begin with o. The words with subject 'you:PLUR' are all of the remaining words; they all begin with bo. So we can conclude

  • o- 'you:SING'
  • bo- 'you:PLUR'

Thus all of the subject morphemes are prefixes, appearing at the beginning of the words.

The following list includes verbs in different TAM forms. (Only forms with subjects 'I', 'you:SINGULAR', and 'he/she' are included; the other subject morphemes behave similarly.) You need to figure out what the verb roots and the TAM morphemes are. (Also refer to the words in the first list.)

Word Root Subject TAM
nakokoma write I FUT
nakokóma arrive I FUT
okosómba buy you:SING FUT
akosómba buy he/she FUT
nakotúna ask I FUT
okoloba speak you:SING FUT
akondima agree he/she FUT
akoyébisa tell he/she FUT
nakokabola divide I FUT
okotatabana be:surprised you:SING FUT
akotámbwisa drive he/she FUT
nakopangwisa wipe I FUT
nákoma write I SUBJ
ókoma write you:SING SUBJ
ákoma write he/she SUBJ
násómba buy I SUBJ
ókóma arrive you:SING SUBJ
ákabola divide he/she SUBJ
nátámbwisa drive I SUBJ
óbóngola change you:SING SUBJ
ásepela enjoy he/she SUBJ
náyébisa tell I SUBJ
nakomí write I PRES PERF
okomí write you:SING PRES PERF
akomí write he/she PRES PERF
akómí arrive he/she PRES PERF
nasómbí buy I PRES PERF
ondimí agree you:SING PRES PERF
obóngólí change you:SING PRES PERF
nabóngólí change I PRES PERF
atámbwísí drive he/she PRES PERF
otámbwísí drive you:SING PRES PERF
nayébísí tell I PRES PERF
ayébísí tell he/she PRES PERF
osepélí enjoy you:SING PRES PERF
natatábání be:surprised I PRES PERF
otatábání be:surprised you:SING PRES PERF
okabólí divide you:SING PRES PERF
akabólí divide he/she PRES PERF
opangwísí wipe you:SING PRES PERF
  1. What are the root morphemes with the following meanings?
    1. write
    2. arrive
    3. look
    4. agree
    5. speak
    6. buy
    7. change
    8. drive
    9. tell
    10. divide
    11. wipe
    12. be surprised
  2. What are the following TAM morphemes?
    1. SIMPLE PRESENT
    2. FUTURE
    3. SUBJUNCTIVE
    4. PRESENT PERFECT
  3. Given what you know about Lingala verb morphology, how would you say the following?
    1. look + you:PLUR + FUT
    2. wipe + we + SUBJ
    3. plead + I + PRES PERF
Let's start as before looking for pairs of words that differ by only one morpheme. The first two words, nakokoma and nakokóma, differ only by the root morpheme, and their forms differ only by the tone on one syllable. But it is unlikely that the root is represented only by the tone on one syllable (since there will be many different roots). So maybe this is just a coincidence because of a similarity between these two particular roots. Further down, there three other words that differ from these only by the root, nakotúna, nakokabola, and nakopangwisa. Now we see that the part that distinguishes the forms is the part following nako and preceding the a at the end. So we can tentatively propose the following:

  • -kom- 'write'
  • -kóm- 'arrive'
  • -tún- 'ask'
  • -kabol- 'divide'
  • -pangwis- 'wipe'

Now let's check different words with each of these root morphemes to see if they all share the forms that we're proposing. There are no others for 'ask', but for 'write' and 'arrive' the morphemes we proposed are found in all of the words. For 'divide' and 'wipe', however, there are a few words where the tones differ: okabólí, akabólí, and opangwísí. The tones on the first syllables of the forms we proposed agree (all are low), but on the second syllable, they are sometimes low and sometimes high. Maybe the tone on the second syllable is not part of the root morpheme, but part of the TAM morpheme instead.

Let's continue to look for more roots as we have been, this time looking for all words that share a particular root. For example, all words with the meaning 'buy' have sómb right before the final vowel. In several cases, we again discover that roots that appear to have more than one syllable have different possible tone patterns: for 'change' we find both bóngol and bóngól, for 'drive' both támbwis and támbwís, for 'enjoy' both sepel and sepél, for 'be;surprised' both tataban and tatábán. Again the first syllables always agree, while the other syllables can be either high or low. So here are the additional roots we propose, with the understanding that the tone on any syllables after the first is not specified in the root. (We can figure out the roots that have only example by looking for "minimal pairs" or "near minimal pairs" with other roots.)

  • -ndim- 'agree'
  • -sómb- 'buy'
  • -sepel- 'enjoy'
  • -bóngol- 'change'
  • -támbwis- 'drive'
  • -yébis- 'tell'
  • -tataban- 'be:surprised'
  • -tál- 'look'
  • -lob- 'speak'

Now let's try to figure out the TAM morphemes (the hardest part). Since we know whether the subject morphemes come, and we think we know what the root morphemes, the TAM morphemes should be whatever is left. One part that we haven't included in either the subject or root is the final vowel. Notice that this is a in all cases except when the TAM morpheme is PRES PERF. So we can propose that the following are at least parts of the TAM morphemes.

  • -a 'SIMPLE PRESENT, FUTURE, SUBJUNCTIVE'
  • 'PRESENT PERFECT'

Now let's look at some "minimal pairs". The SIMPLE PRESENT and SUBJUNCTIVE look very similar, so they might be good to start with. One pair is nakoma and nákoma, the first SIMPLE PRESENT, the second SUBJUNCTIVE. It looks like the SUBJUNCTIVE makes the tone on the subject prefix high. Let's look at the other SUBJUNCTIVE examples to see if this holds. Sure enough, all have high tone on the subject prefix. So now there are two ways we can say this. One is to say that the tone on the subject prefix is specified by the TAM morpheme: it is low for SIMPLE PRESENT, FUTURE, and PRESENT PERFECT and high for SUBJUNCTIVE. The other is to say that subject prefix has low tone but that this gets changed to high in the SUBJUNCTIVE (an example of mutation). Given the data here, either would be reasonable.

Now let's try to figure out the future. Comparing it with the SIMPLE PRESENT (there are several "minimal pairs"), we can conclude that the FUTURE has an additional syllable -ko- following the subject prefix. (This is also a prefix because it precedes the root.)

Now for the PRESENT PERFECT. So far it seems to consist of just the suffix . But if we compare the SIMPLE PRESENT/PRESENT PERFECT "minimal pairs" such as okabola / okabólí, natatabana/natatábání, nabóngola/nabóngólí, atámbwisa/atámbwísí, we see that the suffix is not the only difference. In fact, if we look carefully, we see that for the PRESENT PERFECT, the root syllables following the first one always have high tone, whereas these same syllables always have low tone for the other TAM morphemes. Again there are two ways to describe this. Either the tone of these syllables is part of the TAM morpheme in all cases: low for SIMPLE PRESENT, FUTURE, and SUBJUNCTIVE and high for PRESENT PERFECT. Or these syllables have low tone in the root, and PRESENT PERFECT makes the tone high. Notice that the first option is appealing because it has those root syllables agreeing in tone with the suffix, an assimilation-like process.

So here are the TAM morphemes we come up with (one of several possible descriptions).

  • The tone of root syllables after the first agrees with the tone of the suffix.
  • -a 'SIMPLE PRESENT'
  • -ko- immediately after subject prefix, -a 'FUTURE'
  • -a, high tone on subject prefix 'SUBJUNCTIVE'
  • 'PRESENT PERFECT'

And now we should be able to put these together to make the novel words in 5.

  1. bokotála 'look + you:PLUR + FUT'
  2. tópangwisa 'wipe + we + SUBJ'
  3. nabóndélí 'plead + I + PRES PERF'

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