द्रव्ययज्ञास्तपोयज्ञा योगयज्ञास्तथापरे।स्वाध्यायज्ञानयज्ञाश्च यतयः संशितव्रताः॥
dravya-yajñās tapo-yajñā yoga-yajñās tathāpareswādhyāya-jñāna-yajñāś ca yatayaḥ sanśita-vratāḥ
Word by word
The verse says
Some offer what they own. Some offer hard practice. Some offer the disciplines. Some offer study and knowing - people who have taken firm vows and hold to them.
In plain words
Four more, and they are recognisably ordinary.
Wealth. Austerity. The practices. Study.
Saṁśita-vratāḥ - of sharpened vows. People who have decided something and hold to it.
Where you've felt this · in study
Four people live in the same building. One gives money away and never mentions it. One is up at five every morning. One does her practice every single day. One is still working through the same texts after thirty years.
Going deeper
Svādhyāya - self-study, or study of what has been handed down. The word carries both senses, and that doubleness is old.
What makes this verse useful is how unexotic the list is. Giving money. Doing without. Keeping a practice. Reading carefully. These are available to almost anyone, and Krishna puts them in the same category as the breath disciplines of the verse before.
Saṁśita-vratāḥ - those whose vows are sharpened, honed. The metaphor is of an edge, and it suggests something maintained rather than merely declared.
The catalogue's cumulative effect is what matters more than any item on it. By the end of it, yajña covers wealth, body, breath, senses, attention and study, performed by householders, ascetics and everyone between.
Which is how the Gita takes a word that meant a fire ritual performed by specialists and makes it a description of any life lived with something given rather than held.