Concentus tibiae et citharae matri gratior est quam tibia sola.

The subject is concentus.

• It is nominative singular.
• It means something like harmony, playing together, or musical combination.
• The verb est is singular because concentus is singular.

So the basic frame is:

• Concentus ... est = The harmony/combination ... is

They are both genitive singular, depending on concentus.

So:

• concentus tibiae et citharae = the harmony of the pipe and the lyre

This is a very common Latin pattern: a noun followed by another noun in the genitive to show of.

A beginner may notice that tibiae could also look like nominative plural, and citharae could also have other possible meanings in isolation. But here the syntax makes the meaning clear:

• concentus is the main noun
• tibiae et citharae tells us whose / of what kind harmony it is

Because gratus and its comparative gratior regularly take the dative of the person pleased.

So:

• matri gratior est = is more pleasing to the mother

This is a very important Latin pattern:

• gratus alicui = pleasing/welcome to someone

So Latin does not say this with a preposition like to; it simply uses the dative case.

Gratior is the comparative form of gratus.

Here it means:

• more pleasing
• more welcome
• more agreeable

A native English speaker may first think of grateful because of the similarity, but here that is not the meaning. In this sentence, gratior means more pleasing, not more thankful.

Because it agrees with concentus.

• concentus is masculine singular nominative
• gratior is masculine/feminine singular nominative comparative

So the agreement is correct:

• concentus ... gratior est

If the subject were neuter, the comparative form would be different.

This is the comparative part of the sentence.

• quam = than
• tibia sola = the pipe alone

The full idea is something like:

• Concentus tibiae et citharae matri gratior est quam tibia sola [est].
• The combination of pipe and lyre is more pleasing to the mother than the pipe alone [is].

Latin often leaves out words that are easy to understand from context. Here, a form of est is understood after tibia sola.

Because tibia sola is understood as the subject of an omitted clause.

In other words, Latin is really comparing:

• concentus ... est with
• tibia sola [est]

So tibia stays in the nominative, just as concentus is nominative.

This is a very common thing with quam in comparisons: Latin can compare two things in the same case.

Latin often has two ways to make a comparison with a comparative adjective:

1. comparative + ablative
2. comparative + quam

Here we get quam.

Why? Because quam is especially natural when the comparison is really shorthand for a fuller clause:

• ... gratior est quam tibia sola [est]

Using quam makes the comparison clearer and more explicit. It is often preferred when the structure is a little fuller than a simple noun-to-noun comparison.

Sola modifies tibia.

• tibia sola = the pipe alone

It is:

• nominative singular feminine
• agreeing with tibia

As for word order: Latin adjectives can come before or after the noun. Both are common. So tibia sola is perfectly normal Latin.

Because the sentence is talking about one combined musical effect.

It is not saying:

• the pipe and the lyre are more pleasing

Instead it says:

• the harmony / combined sound of the pipe and lyre is more pleasing

So the two instruments produce one concentus, and that noun is singular.

Because Latin has no articles like English the or a/an.

So Latin simply says:

• concentus tibiae et citharae
• matri
• tibia sola

English must choose whether to say the, a, or sometimes nothing, based on context. Latin leaves that unstated.

The word order is fairly flexible, but it is not random.

This sentence is arranged quite naturally:

• Concentus first: the topic or subject
• tibiae et citharae next: specifying what kind of concentus
• matri before gratior: placing the person affected close to the adjective
• quam tibia sola at the end: the comparison comes last

A more rigid English-style order is not required in Latin, because the case endings show the grammar. Word order often helps with emphasis, flow, and style, rather than basic grammatical clarity.