ॐ पूर्णमदः पूर्णमिदं पूर्णात्पूर्णमुदच्य-ते ।पूर्णस्य पूर्णमादाय पूर्णमेवावशिष्य-ते ।ॐ खं ब्रह्म ।खं पुराणं वायुरं खमि-ति ह स्माह कौरव्यायणीपुत्रो वेदोऽयंब्राह्मणा विदुर्वेदैनेन यद्वेदितव्यम् ॥
In plain words
Om. That is whole. This is whole. Wholeness comes forth from wholeness. Take wholeness from wholeness, and wholeness alone is left standing. Om. Space is Brahman. Space is the oldest thing there is; wind, too, is space -- so declared the son of Kauravyāyaṇī. This is the Veda. The brahmins know it, and through this Veda they know everything there is to know.
Close to the Sanskrit
Om. That is full; this is full. From the full, fullness arises. Taking the fullness of the full, fullness alone remains. Om. Space is Brahman. Space is ancient; wind is space -- thus indeed said the son of Kauravyāyaṇī. This is the Veda; the brahmins know it; by this Veda, whatever is to be known [is known].