stratagem

n. 谋略，策略

strait-jacket, strait-laced, straitened, strand, stranded, strange, strangely, strangeness, stranger, strangle, stranglehold, strangler, strangulate, strangulation, strap, straphanger, strapless, strapped, strapping, strata, strategic, strategically, strategist, strategy, stratification, stratify, stratoscope, stratosphere, stratum, straw, straw poll (also straw vote), straw-coloured, strawberry, strawberry-mark, stray, stray away from, streak, streaker, streaky, stream,