Guidelines regarding e>i and e>ie stem-changes in Spanish "-ir" verbs
The overwhelming majority of Spanish verbs ending with "-e*ir", change that 'e' either into 'i' or into 'ie' in their present-tense singular and in the third person plural. That^ asterisk * can represent one or two consonants, or even no consonant (so the above statement also applies to "-eír" verbs).
The only exceptions are the three which terminate in "-ergir":
sumergir, divergir, and convergir, and the rarely used enjerir.
(Defective "-e*ir" verbs - which never use those^ present tense forms, namely agredir, transgredir, preterir, aterir and aguerrir - cannot be regarded as exceptions).
Is it possible to find a rule or pattern which will make it easier to learn how those verbs change? For me personally, it is helpful to remember, for example, that advertir, convertir, invertir, divertir and the others which end in "-vertir", all adopt the e>ie stem-change in the present tense.
With the help of my CLAVE dictionary (Ediciones SM), whose
accompanying CD offers a 'reverse alphabetic' option for examining words,
a few generalisations emerged:
1. "-e*ir" verbs which change that 'e' into 'i':
All which end in "-etir" (repetir, etc. i.e., 'yo repito', 'ellos repiten'; but of course 'nosotros repetimos').
All which end in "-egir" (elegir, corregir, etc.)
All which end in "-edir" (medir, pedir, etc.)
All which end in "-eír" (reír, freír, etc.)
Seguir and verbs derived from it by adding a prefix (e.g. conseguir). 'Erguir' also follows this pattern: (yo i.rgo, ellas i.rgen - although 'yergo' etc. are used sometimes). These can of course be regarded as "-e*ir" verbs, just like all the others - because the 'u' after the 'g' is silent -i.e., the 'gu' acts just as a consonant.
Decir and verbs derived from it by adding a prefix, such as bendecir, predecir - but remember the 'digo' irregularity.
All which end in "-eñir" (reñir, etc.)
All which end in "-estir" (vestir(se), etc.)
Plus: concebir, gemir, rendir(se), henchir, and two in
"-ervir": servir and hervir.
2. "-e*ir" verbs which change that 'e' into 'ie':
This pattern is followed by almost all "-e*ir" verbs which do not belong in category 1 above; e.g. convertir, preferir, mentir, sugerir, sentir: ('yo siento', 'ellos sienten').
Venir may also be included under this heading (as long as you remember its 'vengo' irregularity), together with verbs derived from it such as intervenir, convenir and prevenir.
The only important exceptions are the three "-ergir" verbs which were mentioned earlier.
It is worth adding that there are two "-irir" verbs in
Spanish, adquirir and inquirir (which used to be spelled 'adquerer' etc.):
they too adopt this "ie" stem-change, i.e. 'yo adquiero';
(but nosotros adquirimos).
3. Preterite tense:
All e>i verbs, and almost all e>ie ones, change their stem to "i" in the third person preterite; e.g. 'ella repitió', 'ellos pidieron'; 'él sintio'.
But there are three "-cer.nir"
discernir, concernir, cernir(se) ... plus hendir,
which do not change the stem to "i" in the third person preterite - e.g., disce.rnió.
However, those four verbs follow the present-tense pattern shown in 2 above, e.g. 'yo discierno'.
The defective verbs form their preterites like those ending
in "-cer.nir", for example
'agredieron' (they attacked), not 'agridieron'.
David L. McNaughton
Home Page: www.DLMcN.com
Sustantivos con terminaciones en -ía en lugar de -ia ... http://DLMcN.com/iawords.doc
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