his/her handwriting
En revanche, son écriture était magnifique, et elle écrivait très vite.
On the other hand, her handwriting was beautiful, and she wrote very quickly.
Je n'arrive pas à lire son écriture.
I can't read their handwriting.
Son écriture penche vers l'avant, alors que la sienne penche vers l'arrière.
His handwriting slants forward, whereas hers slants backward.
J'ai un modèle de son écriture.
I have a model of his handwriting.
This isn't their handwriting.
This is his writing.
Parfois son écriture en anglais ressemble à du russe.
Sometimes their writing in English looks like Russian.
— Des étoiles sur la terre (2007)
Il est impossible de lire son écriture.
It is impossible to read his handwriting.
His handwriting is illegible.