Yusuf Ali
We know indeed that they say, "It is a man that teaches him." The tongue of him they wickedly point to is notably foreign, while this is Arabic, pure and clear.

Sahih International
And We certainly know that they say, "It is only a human being who teaches the Prophet." The tongue of the one they refer to is foreign, and this Qur'an is [in] a clear Arabic language.

Shakir
And certainly We know that they say: Only a mortal teaches him. The tongue of him whom they reproach is barbarous, and this is clear Arabic tongue.

Pickthall
And We know well that they say: Only a man teacheth him. The speech of him at whom they falsely hint is outlandish, and this is clear Arabic speech.

محمد جالندھری
اور ہمیں معلوم ہے کہ یہ کہتے ہیں کہ اس (پیغمبر) کو ایک شخص سکھا جاتا ہے۔ مگر جس کی طرف (تعلیم کی) نسبت کرتے ہیں اس کی زبان تو عجمی ہے اور یہ صاف عربی زبان ہے