Ego, cum amicam flentem video, saepe suspiro quoque et quaero quid illi desit.

Yes. In Latin, the ending of suspiro already tells you the subject is I, so ego is not grammatically necessary.

When Latin includes ego, it is usually for one of these reasons:

• emphasis: I sigh
• contrast: I sigh, maybe unlike someone else
• clarity: to make the subject especially obvious

So ego here adds a little stress to the speaker’s personal reaction.

Here cum means when, introducing a temporal clause.

That is why the verb is video in the indicative, not the subjunctive. The clause is simply stating the circumstance in which the main action happens:

• cum amicam flentem video = when I see my friend crying

Learners often meet another kind of cum that means since, although, or sometimes a more literary when, and that one often takes the subjunctive. But this sentence uses the straightforward temporal cum + indicative.

Because flentem goes with amicam, and amicam is the direct object of video.

Latin often uses a present participle to describe the noun it belongs to:

• amicam = female friend in the accusative singular
• flentem = crying, also accusative singular feminine

So amicam flentem means my friend crying or my crying friend.

The participle must match the noun it describes in:

• gender
• number
• case

That is why it is flentem, not flens.

Latin very often uses a participle where English might prefer a clause.

So instead of saying something like:

• when I see that my friend is crying

Latin can say more compactly:

• cum amicam flentem video

This is a very normal Latin way to express what someone sees, hears, or finds:

• video puerum currentem = I see the boy running
• audio feminam cantantem = I hear the woman singing

So this construction is natural and common.

Quoque means also or too.

In Latin, quoque usually comes after the word it especially connects with. So:

• suspiro quoque = I also sigh / I sigh too

That post-position is very normal for quoque. English usually puts also before the verb or too at the end, but Latin commonly places quoque right after the emphasized word.

Because it is an indirect question.

The direct question would be:

• quid illi deest? = what is lacking to her? / what does she lack?

But after a verb like quaero (I ask, I wonder, I inquire), Latin normally puts the indirect question in the subjunctive:

• quaero quid illi desit = I ask/wonder what she lacks

So desit is subjunctive because the question is reported or embedded, not asked directly.

Because the verb desum, deesse works with the dative, not a direct object.

Literally, deest alicui means:

• it is lacking to someone

So:

• illi deest = it is lacking to her
• more naturally in English: she lacks it or something is missing for her

That is why Latin uses illi (dative singular) rather than an accusative form like eam.

Desit is:

• 3rd person singular
• present subjunctive active
• from desum, deesse, defui

The verb desum is built from:

• de-
  • sum

Because it is related to sum, some of its forms look unusual if you are expecting a regular verb.

Here:

• deest = is lacking
• desit = may be lacking / in this sentence, subjunctive because it is in an indirect question

Illi here is the dative singular form of ille, illa, illud.

In this sentence it means to her.

Since amicam is feminine singular, illi naturally refers back to that female friend:

• amicam flentem = my female friend crying
• quid illi desit = what may be lacking to her

Learners sometimes confuse illi with plural forms, because illi can also mean those or to/for those in other contexts. But here the sense is clearly to her.

Grammatically, amica simply means female friend.

Depending on context, it can sometimes mean:

• girlfriend
• beloved
• female companion

But by itself, it does not have to mean a romantic partner. The surrounding context decides that. In a learner sentence like this, it is safest to understand it as female friend unless the wider passage suggests romance.

Latin word order is much freer than English word order because Latin relies heavily on case endings and verb endings to show grammatical relationships.

So in this sentence:

• Ego, cum amicam flentem video, saepe suspiro quoque et quaero quid illi desit.

the endings tell you who is doing what:

• video, suspiro, quaero = I do these actions
• amicam = object of video
• flentem = describing amicam
• illi = dative with desit

The order is not random, though. Latin often arranges words for:

• emphasis
• rhythm
• style
• keeping related words near each other

For example, amicam flentem keeps the noun and its participle together, and quid illi desit keeps the indirect question as a unit.

Yes, to a large extent. Because the endings carry the grammar, Latin can often reorder words without changing the basic meaning.

For example, these would still be understandable Latin:

• Cum amicam flentem video, ego saepe suspiro quoque et quaero quid illi desit.
• Ego saepe suspiro quoque et quaero, cum amicam flentem video, quid illi desit.

However, different order can change:

• emphasis
• flow
• style

So while the basic meaning remains the same, the original order is probably chosen to sound natural and to highlight the speaker’s reaction in a smooth sequence.