Jennifer's answer:

Adjectives must agree with the nouns they modify in gender, as well as case and number. One kind of adjective declines like a second declension noun when it modifies masculine or neuter nouns, and like a first declension noun when it modifies feminine nouns. So you'd have puella parva, but puer parvus.

Scott's answer:

But remember that it is agricola parvus.

Sebastian's answer:

This technique works for the moment, because only the first two declensions have been introduced, but, be careful to not over-generalise the method. Even at this early stage, there are traps. For instance, it is in general true that nouns in -a in the nominative belong to the first declension, but a noun like 'arma' (arms) ends in -a but is in fact a plural noun of the second declension.

Similarly, that a noun ends in -us in the nominative is insufficient to conclude that it is a second declension noun. For instance, 'corpus' (body) is a noun of the third declension and 'manus' (hand) a noun of fourth declension. Similarly, nouns in -er need not necessarily be second declension, e.g., 'pater' (father) from the third declension.

In general, you need to know the genitive to determine the declension of a noun. So, 'agricola, agricolae' tells you that it is a noun of the first declension, but not 'arma, armorum' since you know that first declension nouns have genitive singular in -ae (although, 'tenebrae, tenebrarum' (darkness) is of the first declension as well despite the genitive in -arum as 'tenebrae' is a plural noun). Similarly, 'amicus, amici' and 'puer, pueri' are second declension, but not 'corpus, corporis', 'manus, manus' and 'pater, patris' since regular second declension nouns have genitives in -i. (Note that the neuter nouns of the second declension in -um, e.g., 'donum, doni', also have genitives in -i. Again, nominative ending in -um is insufficient to guarantee second declension.)

Anyway, back to the original question of how one determines the declension of a noun in context. The short answer, as I have said before, is 'you have to know it'. For instance, 'Lauda mores populi.' Praise the delay of the people? This is, of course, incorrect, and you will only realise it if you know that 'mora, morae', i.e., delay, belongs to the first declension, and can therefore not have a form in -es. The correct reading is 'praise the character of the people', 'mores' from 'mos, moris', a third declension noun. Again, 'naves ex portu educunt'... They educate the ships from the gate? If you know that 'porta, portae' (gate) is from the first declension, and 'educo, -are' (to rear, educate) from the first conjugation, then, you'll realise that they don't have forms in -u and -unt respectively, so this reading is incorrect. The correct reading is of course 'they put the ships to sea' (i.e., they lead the ships out of the port), 'portu' from fourth declension noun 'portus' (port) and 'educunt' from third conjugation verb 'educo, -ere'. In both of these examples, if you hadn't known the declensions of 'porta', gate, and 'mora', delay, a priori, you might well have come to the conclusion that they were of the third declension and fourth declensions respectively from their morphology.

Sebastian's answer:

Generally, you can tell from the context. We do this in English too; for instance, 'bank' is both a financial institution and the side of a river. How do you tell what the word means when you encounter it?

Given an arbitrary word in context, you need to know what the possibilities are for that word. This is why you need to know which declension nouns belong to from the start. It is generally too late to try to figure out the declension of a noun from a text you're reading (although this is often possible), because knowledge of the declension of a noun a priori helps you to decode the syntax with the aid of the context. (This principle applies to the morphology of all the inflecting parts of speech, esp. verbs, nouns and adjectives.)

Take an English example of 'axes' in 'the major and minor axes of an ellipse'. Now, the obvious interpretation of 'axes' would be the plural of 'axe', and, if this is the only possibility you think of, then the phrase would make little sense: why should an ellipse have a axe? The correct interpretation, of course, is that 'axes' is the plural of 'axis', but unless this possibility occurs to you, then you are hard pressed to decode the phrase. Consider 'to found a city', which creates a grammatical problem if interpreted as the past tense of 'find', or 'to fell a tree' as the past tense of 'fall'. This applies to other languages too, e.g., French 'Je vous suis partout.' I am you everywhere? No, more likely, I follow you about, 'suis' being a part of 'suivre' rather than 'être'. 'Les poutres étaient la maison.' The beams were the house? More likely is 'The beams hold up the house.', 'étaient' from 'étayer' rather than the more obvious 'être'.

This applies to Latin too: often, you get hung up on one possible interpretation of a given word, and fail to make any sense of the sentence. For instance, 'Viator est alienum cibum'. A traveller is foreign food? Likelier: a traveller eats foreign food, 'est' from 'edo' rather than 'sum'.

In summary, then, to discover the meaning of a word that can mean several things:

1) Be familiar with its declension/conjugation so as to avoid introducing extraneous (erroneous) interpretations by mistaking a word for a similar word, e.g., mora/mos, porta/portus, educare/educere. Perhaps there is only one possibility after all.

2) Consider all the possibilities for a given word by not restricting it to the most obvious root word, e.g., for 'est', don't immediately conclude that it is a part of 'sum', but think whether it might be part of another word like 'edo'.

3) Use the context in which the word occurs to narrow the possibilities. By context, I refer to both syntactic and semantic context. For instance, the semantic context of 'Viator est alienum cibum.' makes 'est' as a part of 'sum' unlikely. The syntactic context of 'Verbum deum est veritas.' makes 'deum' as accusative singular unlikely, despite the fact that this is the only possibility for 'deus' if one does not realise that it is irregular.

Jennifer's answer:

fIlia
fIliae
fIliae
fIliam
fIliA

fIliae
fIliArum
fIliabus
fIliAs
fIliabus

You decline 'fIlia' just like a regular 1st declension noun except that the dative and ablative plural forms are usually changed so as not to confuse them with those same forms of 'fIlius' - you don't want to confuse the sons with the daughters, which you easily could if you used 'fIliIs' for both.

Sebastian's answer:

David C.'s answer:

Mea filia can be either nom. or voc. since Wheelock (p. 11) says:

... [in the first declension] the vocative has the same form as that of the nominative. -W

But I think it is vocative because of the previous line:

In modern punctuation the vocative is separated from the rest of the sentence by commas. - W

The author of the book wants to insert an exercise on the voc. here. But if I heard the line rather than read it, I would translate it as:

My daughter is forever saying her friends know it all.

Michael Myer's answer:

WRT Ch 3 PR 3: Sapientiam amicarum, filia mea, semper laudat. I'd like to offer the following:

Yes, with the commas separating out the mea filia, it should be regarded as vocative. In this case, an analysis & translation would go something like:

Sapientiam amicarum, filia mea, semper laudat.
acc - DO gen-poss voc-DA adv 3rd sg pres
wisdom of friends o daughter mine always s/he praises

My daughter, [I tell you now that] he always praises the wisdom of friends.
He always praises the wisdom of friends, my daughter.

Without the commas, that filia mea would instead look like a nominative subject, and the result would be closer to:

Sapientiam amicarum filia mea semper laudat.
acc - DO gen-poss nom - S adv 3rd sg pres
wisdom of friends my daughter always she praises

My daughter always praises the wisdom of friends.
My daughter always praises her friends' wisdom.

They are adjectives. Like any other adjectives, they need to agree with the word they're modifying in number, gender and case. They are like the other Chapter 3 adjectives -- if they are modifying a masculine noun, they use second-declension endings; if they are modifying a feminine noun, they use first-declension endings. Even though you are a woman, you would speak of "Meus filius", "my son", and, to speak of his daughter, your husband would say, "mea filia".

The only time your being a woman matters when you're using Latin is if you want to use an adjective to describe *yourself*. "I'm tired." "I'm cross." I'm happy." You and I would say, "Fessa sum." "Irata sum." "Laeta sum," where Kirk and Michael and Ernie would say, "Fessus sum." "Iratus sum." "Laetus sum." ("Sum" means "I am")

David C.'s answer:

Yes to the first two questions, and yes to the third question.

I am guessing that since there is a choice concerning word order in the phrase, the emphasis in certain orderings would be different, as follows:
'in vitis filiarum' => It is in the daughters (rather than the sons);
'in filiarum vitis' => It is in their very lives.

The phrase needs a 'tuarum' in there for the 'your' in genitive plural.

So,
'we see' becomes videmus,
'great fortune' becomes 'fortunam magnam' or 'magnam fortunam',
'in lives' becomes 'in vitis',
'of your daughters' becomes 'tuarum filiarum' or 'filiarum tuarum',
'my friend' becomes 'mi amice'.

Putting it together lyrically would give:

Magnam fortunam, amice
mi, tuarum videmus
in filiarum vitis.

Michael Myer's answer:

The first (and least enlightened) rule is that any masc + fem mixed-gender group becomes masculine. Throw one guy into a classroom full of girls and you have to call them either "discipuli" or "disciplae et discipulus."

But there is another force at work with the adj + noun et noun pattern: attraction. It is always possible with compound nouns for the adjective to be attracted into the case, number, and gender of the nearest noun to it.

So the phrase "my daughter and son" could appear as "mei filia et filius", but I would not at all be surprised to instead see "mea filia et filius."

Now as to your example, with plural dative indirect objects "filiabus et filiis", the form will be idetical no matter how you imagine it in the privacy of your own brain. For meus a um, the dative plural forms in masc fem & neut are ALL "meis." So think of it as masculine or think of it as feminine, it matters not this time. Run, fly, be free.

Bob's answer:

The "et ....et construction translates as :"both....and..."

Hence sentence translates as " The farmer often praises both the life and fortune of the sailor."

David Goldfarb's answer:

It's not a nominative plural. (If memory serves me right, "malum" is a neuter noun, so the nominative plural would be "mala". You guys haven't had 2nd declension neuters yet....) It is a genitive singular -- "fOrmae malI", "forms of evil". I translated it as "Many kinds of evil..." After that you're ok.