Learn Hardcore French: Tes bottes sont lourdes, mais ton écharpe est légère. - Your boots are heavy, but your scarf is light.

tes = your (plural), used with any plural noun → tes bottes (boots = plural)
ton = your (masculine singular), but it’s also used before a feminine singular noun that begins with a vowel sound for ease of pronunciation → ton écharpe (écharpe starts with a vowel sound)

But isn’t écharpe feminine? Why not ta écharpe?

Yes, écharpe is feminine. Normally you’d use ta, but before a vowel sound (or a mute h), French switches ta/ma/sa to ton/mon/son to avoid a hiatus. So you say ton écharpe. Note: this switch does not apply to words with an “aspirated h” (marked in dictionaries); there you keep ta/ma/sa and make no liaison.

What’s going on with the adjective endings: lourdes vs légère?

Adjectives agree in gender and number with the noun:

bottes (feminine plural) → lourdes (add -e for feminine, -s for plural)
écharpe (feminine singular) → légère (feminine singular form)

Why does the spelling change from léger to légère?

The masculine is léger; the feminine is légère. The accent changes to è to reflect the vowel sound shift, and the final silent e marks the feminine form. Plurals add -s: légers/légères.

Why sont in the first clause and est in the second?

The verb être agrees with the subject:

bottes (plural) → sont
écharpe (singular) → est

Could I put the adjectives before the nouns (e.g., les lourdes bottes)?

Here, the adjectives follow être, so they must come after the verb. When used directly with the noun, most adjectives like lourd/légère normally follow the noun: des bottes lourdes, une écharpe légère. Only a limited set (often remembered as BANGS: beauty, age, number, goodness, size) typically come before the noun.

Is the comma before mais required?

It’s common and stylistically natural in French to place a comma before mais to mark the pause, but it isn’t strictly mandatory in a short sentence like this. Both with and without the comma are acceptable.

Could I use something other than mais?

Yes, depending on nuance:

tandis que / alors que (while/whereas, contrast over time or situation)
par contre (on the other hand)
en revanche (by contrast, a bit more formal)

Do I make any liaison in pronunciation?

ton‿écharpe: yes—obligatory liaison after ton; you’ll hear an [n] linking to the vowel.
tes bottes: no liaison; bottes starts with a consonant.
No liaison at lourdes, mais; the final consonants remain silent.

How are the word-final letters pronounced?

bottes: final -s is silent.
lourdes: final -s is silent; the d is also silent in this position.
légère: the final written e marks the feminine but isn’t a separate vowel; the word ends in the sound of -ère.

If I’m speaking formally to one person or to several people, how do the possessives change?

Use votre (singular) and vos (plural):

Vos bottes sont lourdes, mais votre écharpe est légère.

Can I replace the nouns with pronouns?

Yes:

For bottes (feminine plural): Elles sont lourdes.
For écharpe (feminine singular): Elle est légère. Together: Elles sont lourdes, mais elle est légère.

Is there a difference between écharpe and foulard?

Yes. Écharpe is typically a warm, winter scarf. Foulard is a lighter, often decorative or silk scarf. Context determines which sounds more natural.

Any quick tips to remember the genders of botte and écharpe?

Both end in -e, and many (not all) nouns ending in -e are feminine—here that pattern holds: une botte, une écharpe. It’s still best to learn gender with the noun. You can also look at adjective/possessive agreement as a clue in context.

Is there another way to talk about weight besides être + adjective?

Yes. You can use peser:

Ces bottes pèsent lourd. (These boots weigh a lot.)
Cette écharpe est légère or pèse peu (weighs little).