Because du is a contraction of de + le. You only use du when de is followed by the masculine singular definite article le.
For example:
But Marie is a name and does not use le here, so it stays:
not:
Yes, adjectives normally agree in gender and number with the noun they describe. But magnifique is one of those adjectives whose masculine singular and feminine singular forms look the same.
So:
Both use magnifique in the singular.
The plural does change in spelling:
So agreement still exists; it just is not visible here in the singular.
In this sentence, magnifique is not directly before or after the noun inside the noun phrase. It comes after the verb because it is part of the predicate:
If you put the adjective directly with the noun, you would get:
That is possible, but it sounds much more literary or emphatic. The normal, neutral sentence is:
Yes, but the meaning and structure are slightly different.
The c’est version can sound a bit more emphatic or conversational. In a basic grammar sentence, est is the more direct and expected form.
Chant is pronounced roughly like shahn with a nasal vowel.
A few important points:
So it is not pronounced like English chant with a clear final t.
Yes. French very often uses de + noun/name where English uses 's.
Examples:
So for English speakers, this is an important pattern to get used to: French usually prefers de rather than an apostrophe construction.