In trying to explain special scientific and engineering concepts technical writers may find it useful to: (1) use operational definitions; (2) try the explanation out as a speech first; (3) explain the strategy of an investigation before discussing the tactics; (4) concentrate on the introduction of an article or report; (5) express mathematical ideas in English before using symbols; (6) explain the practical application of important equations; (7) use simple but accurate language; (8) use appositives; (9) do not strive for ambiguous variety; and (10) show the reader how the world looks to the expert.