hui4, kuai4 can, be possible, be able to, to assemble, to meet, to gather, to see, union, group, association, to balance an account, accounting
快
kuai4 fast, quick, swift
块
kuai1, kuai4 piece, chunk, lump, (measure word for them), yuan (unit of currency), fast (of a watch), swift, rapid, happy, joyful, soon, quick, (a measure word, for cloth, cake, soap)