silent

a.沉默的，无言的；安静的，不吵闹的

signal-box, signaller (US signaler), signally, signalman, signatory, signature, signature tune (also theme tune), signet, signet ring, significance, significant, significantly, signification, signify, signor, signpost, Sikh, silage, silence, silencer, silent film, silently, silhouette, silica, silicate, silicon, silicon chip, silicone, silicosis, silk, silk-screen printing, silken, silkiness, silkworm, silky, sill, sillabub, silliness, silly, silly (also silly-billy),