How about the
subjunctive, eh? First, the
present subjunctive:
First, start with the present-tense "yo"-form, that is, the first person singular. Chop off the -o ending, and add these endings:
-ar verbs
-e
-es
-e
-emos
-éis
-en
-er and -ir verbs
-a
-as
-a
-amos
-áis
-an
Thus, the conjugations of a couple of regular verbs in the present subjunctive:
amar to love
ame
ames
ame
amemos
améis
amen
temer to fear
tema
temas
tema
temamos
temáis
teman
Conjugation of verbs with irregular "yo"-forms in the present subjunctive:
tener to have
tenga
tengas
tenga
tengamos
tengáis
tengan
conocer to be familiar with
conozca
conozcas
conozca
conozcamos
conozcáis
conozcan
When you start talking about stem-changers, it gets weird. Stem-changers don't have a stem change in the present subjunctive in first and second person plural, with the exception of -ir verbs, which change e>i and o>u in the second and third person plural but normally in the other conjugatons. Phew. If you didn't quite catch that, look at these examples:
pensar to think
piense
pienses
piense
pensemos
penséis
piensen
poder can/to be able to
pueda
puedas
pueda
podamos
podáis
puedan
dormir to sleep
duerma
duermas
duerma
durmamos
durmáis
duerman
A few verbs don't end in -o in the first person singular present conjugation. These have irregular stems in the present subjunctive:
ser to be - "se-"
saber to know - "sep-"
ir to go - "vay-"
haber grammatical have - "hay-"
In addition to changing stems, these two verbs add some accent marks:
estar to be
esté
estés
esté
estemos
estéis
estén
dar to give
dé
des
dé
demos
deis
den
All right kids, got that? Let's move on to the imperfect subjunctive!
To form the
imperfect subjunctive, start with the third person plural
preterite form. Chop off the -ron
ending, then add one or the other of these sets of endings:
"r"-form
-ra
-ras
-ra
-ramos (preceeding vowel gets an accent)
-rais
-ran
"s"-form
-se
-ses
-se
-semos (preceeding vowel gets an accent)
-seis
-sen
Which set of forms you use depends on location. It varies wildly throughout South America, but the "r"-form is found in Mexico and the "s"-form in Spain. The "r"-form is somewhat more common, but you should be familiar with both.
Now that I've bombarded you with all that nonsense, would you like some examples? Thought so.
hablar to talk, examples with "s"-form
hablase
hablases
hablase
hablasémos
hablaseis
hablasen
vivir to live, examples with "r"-form
viviera
vivieras
viviera
viviéramos
vivierais
vivieran
querer to want, examples with "r"-form
quisiera
quisieras
quisiera
quisiéramos
quisierais
quisieran
The verbs "ir" to go and "ser" to be both are irregular in the past subjunctive: they have the stem "fue", thus "fuese/fuera, fueses/fueras", &c. The verbs can only be told apart by context in the imperfect subjunctive.
How about some nice
compound tenses? The subjunctive present
perfect and the subjunctive
pluperfect are really easy. Just use the verb "haber", plus the
past participle of the
main verb. Examples:
Present perfect subjunctive
escribir to write
haya escrito
hayas escrito
haya escrito
hayamos escrito
hayáis escrito
hayan escrito
Past perfect/pluperfect subjunctive
llegar to arrive examples using the "r"-form
hubiera llegado
hubieras llegado
hubiera llegado
hubierámos llegado
hubierais llegado
hubieran llegado
There once existed a
future subjunctive form, but it is now all but
dead. Instead, the
present subjunctive is used.