ثنى بالانجليزي

to form or make something form into a curved shape

ثَنَيْتُ ذِرَاعِيَ تَحْتَ رَأْسِيَ

I curled my arms under my head

ثَنَىْ شَيْئًا أَيْ طَوَاهُ أَوْ لَوَاهُ مُقُرِّبًا طَرَفَيْهِ مِنْ بَعْضِهِمَا

[transitive] twist something (into something) to bend or turn something into a particular shape

ثنى أيّ طوى

[transitive, intransitive] bend (something) if you bend your arm, leg, etc. or if it bends, you move it so that it is no longer straight

نثني ركبنا عندما نصلي.

We bend our knees when we pray.

تشعر بألم عندما تثني ذراعها.

She has pain when she bends her arm.