Here is a short review of noun groups (declensions) before we explain how to express conditions - sentences with "if" or "if not" in them.
1st declension (most numerous). Masculine, end in a broad consonant (one that follows "a", "o" or "u". All form the genitive singular by slenderizing the last consonant. Most form the basic plural in that way, too, and for nearly all those the genitive plural is the same as the basic singular form. Example: an bád (baw*d), boat; an bháid, of the boat; na báid, the boats; na mbád, of the boats.
2nd declension (second most numerous). Feminine and ending in either a broad or slender consonant. The genitive singular ends in "e" or "i". There are various ways of forming the plural. Example: an bhróg, the shoe; na bróige, of the shoe; na bróga, the shoes; na mbróg, of the shoes.
3rd declension. Masculine and feminine. For all, the genitive singular ends in "a". There are various ways of forming the plural. This declension includes many occupations, all with plural ending in "í". Example: an dochtúir, the doctor; an dochtúra, of the doctor; na dochtúirí, the doctors; na ndochtúirí, of the doctors.
4th declension. Masculine and feminine. For all, the genitive singular is the same as the basic form. There are various ways of forming the plural. Example: an bhá, the bay; na bá, of the bay; na bánna, the bays; na mbánna, of the bays.
A few other nouns, some important, are grouped together in a 5th declension that has several distinct ways of forming the genitive and plural. Finally, there are a dozen or so of irregular nouns not fitting into any declension. You already know some forms for most of them.
In English, the sentences " If it is here, she is glad", and "If it is not here, she is sad" tell us that whenever a certain pre-condition exists, a result follows. The word "when" could replace "if" in the sentences, because the pre-condition is entirely possible and can easily happen.
In Irish, these two sentences become:
Má tá sé anseo, tá áthas uirthi (IR-ee). Mura bhfuil sé anseo, tá brón uirthi.
Memorize these two sentences and their meaning.
In the past, the sentences become: Má bhí sé anseo, bhí áthas uirthi; if it was here, she was glad. Mura raibh (rev) sé anseo, bhí brón uirthi; if it was not here, she was sad.
In the future, the sentences become: Má bheidh (ve) sé anseo, beidh áthas uirthi; if it is here, she will be glad. Mura mbeidh (me) sé anseo, beidh brón uirthi; if it is not here, she will be sad.
"Má" (maw*) causes aspiration in an initial aspirable consonant except with "tá" and "deir". "Mura" (MUR-ruh) causes eclipsis, and the dependent form of the verb follows it, such as "raibh" and "???fuil???".
If the pre-condition is impossible or unlikely, the English sentences become: If it were here, she would be glad. If it were not here, she would be sad. "If" remains unchanged, but the verb form "is" changes to "were", so that we will know that the pre-condition is impossible or unlikely.
In Irish, too, the verb form changes, and the word for "if" also changes - to "dá" (daw*). Memorize these two sentences and their meaning:
Dá mbeadh sé anseo, bheadh áthas uirthi (daw* me-YUHK* shay un-SHUH ve-YUHK* AW*-huhs IR-ee); if it were here, she would be glad.
Mura mbeadh (MUR-ruh me-YUHK*) sé anseo, bheadh brón uirthi; if it were not here, she would be sad.
Unlike English, the same verb form serves all tenses in Irish. To indicate that the unlikely condition was in the past or will be the future, words must be added. For example: English "If it had been here, she would have been glad" is "Dá mbeadh sé anseo inné, bheadh áthas uirthi". Remember to add a word or phrase indicating the past or future in these "if" sentences. Examples of such words or phrases: inné, yesterday; ansin, then; anuraidh (uh-NOOR-ee), last year; amárach, tomorrow; an bhlian seo chugainn (un VLEE-in shuh HOO-in), next year.
There are forms in addition to "bheadh", such as "bhéfeá" (VE-faw*), meaning "you would be", but in this lesson we will practice solely with "bheadh", in the third singular person, "he" or ""she" or "it".
Read these sentences out loud and get their meaning:
Dá mbeadh sí anseo, bheadh airgead (AR-i-guhd) agam. Mura mbeadh Seán sa bhaile, bheadh an múinteoir anseo. Bheadh Máire san oifig inné, dá mbeadh an aimsir (EYEM-sheer) go maith. Bheadh an bus mall amárach, mura mbeadh an bóthar oscailte.
Key: If she were here, I would have money. If Seán weren't at home, the teacher would be here. Máire would have been in the office yesterday, if the weather had been good. The bus would be late tomorrow if the road should not be open (or: isn't open, in more usual speech).
Note that the "dá", (if) part, can be first or second in order.
Other forms of "bheadh" are:
Ní bheadh sé; it wouldn't be
An mbeadh sé?; would it be?
Nach mbeadh sé?; wouldn't it be?
Practice with these sentences, going from Irish to English and then from English to Irish again:
Dá mbeadh an bord sa chistin, ní bheadh aon rud eile ann. Bá mbeadh carr agat, an mbeadh eagla ort? Mura mbeadh sí ag foghlaim (FOU-lim) na Gaeilge, nach mbeadh sí sa bhaile anocht? Ní bheadh Séamas ag an doras, mura mbeadh an aimsir chomh dona seo. An mbeadh na doirse oscailte anocht, dá mbeadh na páistí ann?
Key: If the table were in the kitchen, nothing else would be there. If you had a car, would you be afraid? If she weren't studying Irish, wouldn't she be home tonight? Séamas wouldn't be at the door, if the weather weren't this bad. Would the doors be open tonight, if the children were there?