A linguistic theory is constructed about what ______ is and how it works.
A、langueC
语言的研究过程可以总结为：首先，要观察某些语言材料，从而发现一些共性并对其加以总结;其次，根据这些总结提出一些假设来解释这些语言材料，然后再通过进一步的观察来验证这些假设的正确性;最后建立一套语言学理论来说明语言的本质内容以及这些语言是如何发挥作用的。
Thethieftookawaythewoman’swalletwithout________.
Hesaidthatthegroup________himaletterandaskedhimtogothereforaninterview.
Theengineer______myfatherworksisabout50yearsold.
_______isafactthatEnglishisbeingacceptedasaninternationallanguage.
Theothertimingsystembelongsinourinternalclocks，which，left________，wouldtiethebodytoa25-hourrhythm.
