Present conditional (I should…) was formed by interpolating –EHE- for 1^st conjugation verbs, and –OHE- for second conjugation ones. For the past, interpolate –AHE- for all verbs.

Thus:

I should take = lembehen (present conditional); I should sleep = sounohen (present conditional)

I should have taken = lembahen (past conditional)

This was purely literary. There were three tenses.

For the present, interpolate –EXE- or –OXE-. between the root and the (abbreviated) pronomial endings. For the past, use -AXE. For the future, use -EAXE.  Thus:

I must take = lembexen (present necessitative);  I must sleep = sounoxen (present necessitative)

I had to take = lembaxen (past necessitative);   

I shall have to take = lembeaxen (future necessitative)

Other tenses were formed using the indicative of the main verb plus TOUTAUE ("of necessity"). This was also how the present, past and future were formed in the colloquial language.

The imperative mood, being the form of the verb used to give orders in the second person, singular and plural, was formed by the simple root of the verb, followed by the second person (singular or plural) of the present tense of TEH (to do).
Thus:

Take! (singular) = lemb tehetu!

Take! (plural) = lemb tehetes!

This imperative formation could also be used in the first and third persons in a permissive sense, meaning "let..." or "may..." someone do something. Thus:

Let me take / may I take = lemb tehenu
Let him take / may he take = lemb tehe
Let her take / may she take = lemb tese
Let it take / may it take = lemb tehe
Let us take / may we take = lemb tehens
Let them (masc) take / may they take = lemb tehen
Let them (fem) take / may they take = lemb tesen
Let them (neut) take / may they take = lemb tehen

INFINITIVE MOOD

To form the infinitive of a verb, simply prefix EI (or ED if before a following vowel) before the root.

eg: To do = ei teh.
(Ei or ed may be omitted in the literary language if preceded by a vowel at the end of the word before it.)

SUBJUNCTIVE MOOD

This was mostly used in the written language, only, by the time of Classical Atlantean. It was used in "if" clauses, and in certain other places, such as after verbs of saying, believing, doubting, etc. 

There are only three tenses, present, past and future. For the present, interpolate IE or IO between root and endings. For the past, put in IA. For the future, IERA. Note that the pronominal endings which follow are the full forms. Thus:

Present:
If I take, etc = lembienu           If I sleep, etc = sounionu
If we take, etc = lembiens       If we sleep, etc = sounions

Past
If you took, etc (sing) = lembiatu
If you took, etc (plural) = lembiates

Future
If he will take, etc = lembierathe
If they (fem) will take, etc = lembierasen

All the above tenses have been active. There existed also a passive voice (meaning, for example, "it was taken" instead of "it took"). Endings existed for this, in the present, past and future, which were literary and somewhat rare. The method was to interpolate –PHE- between the active indicative  tense vowel and the (abbreviated) personal endings, eg 

Present
I am taken = lembephen
We are taken = lembephens

Past
You (sing) were taken = lembaphe
You (plural) were taken = lembaphetes

Future
He will be taken = lembeapheth
They (fem) will be taken = lembeaphesen

There is also a passive infinitive, with ei / ed  and eph / oph, aph, eaph added to the root for the present, past and future. Thus:
To be taken = ei lembeph.

More common in the colloquial language, and the only method for all other tenses, was to use the (irregular) verb AIS ("to be") in the relevant tense, plus the past participle of the verb. (For the conjugation of irregular verbs like AIS, see the separate section. So:

Perfect
I have been taken = ainu lembaxa

Pluperfect
I had been taken = eanu lembaxa

Future perfect
I shall have been taken = aiseanu lembaxa.

This form of the passive can also be used with the conditional of AIS, but only in two tenses, the present and past, and it is not possible at all with the form using -PH-. 

Present conditional
I should be taken = aisehen lembaxa

I should have been taken = aisahen lembaxa

AUXILIARY VERBS

Atlantean only uses auxiliary verbs in the same way as English in the case of  "to be able", "can".
This is translated by EX plus the infinitive. 

In other cases, Atlantean uses a particular tense or mood, often with an adverb. This is so with:

"To have to", "must"   =   the necessitative mood (literary language), or the indicative + toutaue ("of necessity").

"To be allowed to", "may"  =  the permissive mood, adding "ca malcietu / malcieten" ("if you wish") to the second person of the permissive mood (which would otherwise be an imperative order!) This is for the present tense only. For any other tense, used the relevant indicative tense, plus the corresponding tense and person of "ca malc...", eg "ca malciatu / malciaten" (past, second person) and "ca malcierathe / malcierathen" (future, third person). 

"May / might (possibly)"   =   the indicative tense plus exehe ("possibly")

"Ought to"   =   the conditional mood plus toutaue ("of necessity")

"Should / would"   =   the straight conditional mood.

"..like to.."   =   the indicative mood plus malcehe ("willingly")

"Want to"   =   the conditional mood plus malcehe ("willingly")
To say straightforward "want" something, use the verb malc.