知道

know; tell; see; ken; be aware of; realize; understand; discern; be conscious of; let into; wise up; put wise to; aware; conscious; cognizant; knowledge; awareness; cognizance

了解

understand; see; know; inform; realize; comprehend; wise up; be familiar with; check up; figure out; make sense of; get to know; grasp; appreciate; familiarize; apprehend; fathom; take in; get the picture; take on board; tune in; acquaint oneself with; be onto; wise; understanding; informed; aware; conscious; acquainted; cognizant; knowledge; grip; fix; insight; comprehension; apprehension; acquaintance; onto; tuned in