以及
yǐjí · HSK 4
and
➕ 以 = by/with + 及 = reach/extend → 'with-and-reaching' = as well as
以 means 'by means of/with' and 及 means 'to reach' or 'and'. Together 以及 stacks two connector morphemes for a formal 'and / as well as', used to tack extra items onto a list in writing.
以 — phonetic 㠯 (plow/tool) + 人 (person)
Originally a pictograph of a hand-held plow or tool (㠯), later combined with 人 (person) to suggest 'using' something. The core meaning 'to use' extended metaphorically to 'by means of', 'with', and 'because of'. In modern Chinese it functions mainly as a grammatical particle.
及 — hand 又 reaching person 人
Originally a pictograph showing a hand (又) catching or reaching a person from behind, depicting the act of catching up to someone. The core meaning 'to reach' or 'to catch up to' extended to 'and' (reaching/including more items) and 'in time for'. Modern form simplifies the person and hand into connected strokes.