through [θru] prep. 通过，穿过；经由；透过；凭借 adv. 从头到尾；彻底；自始至终 adj. （电话）接通；通话完毕；有洞的；直达的
through: -through-穿过，通过 → 彻底
来自中英语 thurh，穿过，通过，来自 Proto-Germanic*thurkh，穿过，通过，来自 PIE*tere，弯，转，跨过，词源同 turn，trans-，transport.
late 14c., metathesis of Old English þurh, from Proto-Germanic *thurx (source also of Old Saxon thuru, Old Frisian thruch, Middle Dutch dore, Dutch door, Old High German thuruh, German durch, Gothic þairh "through"), from PIE root *tere- (2) "to cross over, pass through, overcome." Not clearly differentiated from thorough until early Modern English. Spelling thro was common 15c.-18c. Reformed spelling thru (1839) is mainly American English.