Heating in northern cities is centrally supplied in winter.
Tips
usage
gōng covers any 'supply / provide / make available' sense: 提供 (to offer), 供应 (to supply), 供给 (to furnish), 供水 / 供电 / 供暖 (water / power / heating), 月供 (monthly mortgage payment). For ritual offerings and legal confessions, switch to the gòng reading.
mistakes
供养 (to provide for one's elders / financially support) takes gōng; 供养 with the gòng reading means 'to make offerings to gods or ancestors'. Same characters, different reading, different sense — let context decide.
Left indexing person-variant 亻 — anchors 供 as a person-to-person action: a provider supplying someone else, or (in the gòng reading) a worshipper offering to a deity. The human element is essential to both readings of the character.
Right component 共 — supplies the sound (gòng matches the gòng reading; gōng is just a tone shift) AND a perfect bonus meaning: together, shared. Supplying and offering both involve sharing what is yours with another. 共 itself depicts two hands holding up an object jointly.