Le grimpeur met de la magnésie sur ses mains.

Met means puts / applies here. It comes from the verb mettre, which very often means to put, to place, or to put on/apply, depending on context.

So in this sentence, Le grimpeur met de la magnésie sur ses mains literally has the idea of The climber puts/applies chalk on his hands.

Because met is the conjugated form, while mettre is the infinitive.

Here, the subject is Le grimpeur = the climber, which is third person singular, so in the present tense you get:

• je mets
• tu mets
• il / elle / on met
• nous mettons
• vous mettez
• ils / elles mettent

So Le grimpeur met = The climber puts/applies.

Because French usually uses a partitive article when talking about an unspecified amount of something.

Here, de la magnésie means something like some chalk or some magnesium chalk.

Compare:

• Il mange du pain. = He eats some bread.
• Elle boit de l’eau. = She drinks some water.
• Le grimpeur met de la magnésie... = The climber applies some chalk...

If you said just magnésie with no article, that would usually sound incomplete in normal French.

Because magnésie is a feminine singular noun.

The partitive articles are:

• du for masculine singular
• de la for feminine singular
• de l’ before a vowel sound
• des for plural countable nouns

So:

• du fromage (masculine singular)
• de la magnésie (feminine singular)
• de l’eau (before vowel)
• des pommes (plural)

Not exactly in everyday use. In climbing, magnésie usually refers to the white chalk climbers use on their hands, not to the chemical element in a general science-class sense.

So although the word is related to magnesium, in this context it is best understood as climbing chalk.

That is why the sentence means the climber is putting chalk on his hands.

Because sur means on, and the chalk is being applied on the surface of the hands.

So:

• sur ses mains = on his hands

If you used dans, that would mean in, which would not fit this idea.

Because mains is plural.

In French, the possessive adjective agrees with the thing possessed, not with the owner.

So:

• sa main = his/her hand (singular)
• ses mains = his/her hands (plural)

Even though the climber is one person, he has two hands, so French uses ses.

French possessive adjectives do not show the gender of the owner in the way English his/her does. They mainly agree with the noun that follows.

So ses mains can mean:

• his hands
• her hands
• sometimes its hands, depending on context

You know it means his hands here because le grimpeur is understood as male.

Both are possible, but they mean slightly different things.

• Le grimpeur = the climber
• Un grimpeur = a climber

With le, the sentence sounds like it refers to a specific climber or to the climber in the example. With un, it would sound more like introducing a climber for the first time or talking about any climber.

So the choice depends on context, not on grammar correctness.

It is in the present tense, and French present tense can describe both:

• something happening right now
• something that happens regularly / habitually

So this sentence could mean:

• The climber is putting chalk on his hands right now
• or The climper puts chalk on his hands as a regular action

The context tells you which meaning is intended.

Yes. French often likes a reflexive structure with body parts, such as:

Le grimpeur se met de la magnésie sur les mains.

This is very natural because French often uses:

• a reflexive pronoun
• plus the definite article for body parts

So instead of saying on his hands, French often says something more like on the hands, while the reflexive pronoun shows whose hands they are.

That said, Le grimpeur met de la magnésie sur ses mains is still understandable and acceptable, especially for a learner.

A rough English-friendly guide is gran-pur or greem-pur, but neither is perfect.

A few helpful points:

• gr is pronounced as in French, with a throat r
• im here has a nasal vowel, so it is not pronounced like a full English im
• peur sounds a bit like puhr, with the French eu sound

A more IPA-style pronunciation is approximately /ɡʁɛ̃.pœʁ/.

If you want to sound natural, the hardest parts are usually the nasal sound in grim- and the ending -peur.

Mains is pronounced approximately /mɛ̃/.

Important points:

• the ai does not sound like English main
• the n is not fully pronounced as a separate n
• the vowel is nasal

So mains is basically one syllable with a nasal vowel. It sounds quite different from how an English speaker might expect from the spelling.