Definite Article with the Body
A. In simple descriptions of body parts, French uses a definite article where English uses a possessive determiner (e.g. his, my, their):
Il a les yeux bleus. - His eyes are blue.
Elle a les cheveux coupés court. - She has her hair cut short.
B. When people activate parts of their own bodies, French also uses a definite article with the body part:
Il a plissé les yeux. - He screwed up his eyes.
Elle a agité le bras. - She waved.
J'ai baissé la tête en y entrant. - I lowered my head as I went in.
Elle a hoché /secoué la tête. - She nodded/shook her head.
C. When people do things which affect their own bodies, or those of others, the usual construction is a definite article in front of the body part, and a reflexive or indirect object pronoun:
Je me suis fracturé la jambe. - I broke my leg.
Elle s'est fait couper les cheveux. - She had her hair cut.
Je lui serre la main. - I shake his hand.
On lui a coupé la tête. - They cut his head off.
These constructions are also possible with a possessive determiner, as in English, however:
Je prends sa main. - I take her hand.
Elle caresse mes cheveux. - She strokes my hair.
D. When body parts are the subject of a sentence, they usually have a possessive determiner, as in English, rather than a definite article:
Ma tête me fait mal. - My head hurts.
Ses paupières se sont abaissées. - His eyelids lowered.
Leurs regards se sont croisés. - Their eyes met.
E. When descriptions of parts of the body or items of clothing are used adverbially, they are accompanied by the definite article:
l'homme au nez retroussé - the man with the turned-up nose
le comédien au chapeau de paille - the actor in the straw hat
Il parlait, le sourire aux lèvres. - He spoke, with a smile.
When reference is made to one body part, one item of clothing, or one more general personal attribute, but two or more people are involved, the entity is usually referred to in the singular:
Nous nous sommes tous les deux cassés le bras.
We both broke our arms.
Ils ont levé la main droite.
They raised their right hands.
Les étudiants sont priés d'inscrire leur nom de famille à l'endroit prévu.
Students are requested to write their surnames in the space provided.
Ils ont tous accroché leur manteau dans l'entrée.
They all hung their coats up in the entrance hall.
Les jumeaux ont vécu leur vie d'une manière indépendante.
The twins lived their lives independently.