If the ravens (a)   the Tower of London, the kingdom will fall. (如果渡鴉離開倫敦塔，大英帝國將會殞落。)

Because (a)   this legend, King Charles II ordered his people to always keep ravens in the Tower. (因為這個傳說，國王查理二世命令他的人民必須將渡鴉永遠留在倫敦塔內。)

(a)   the Ravenmaster is not easy. (要成為渡鴉大師並不容易。)

It often takes quite a (a)   years of training. (通常需要經過好幾年的訓練。)

Keeping them away (a)   danger is part of his job. (讓牠們遠離危險也是他的工作之一。)

Thanks (a)   the Ravenmaster, these birds are safe and sound. (幸虧有渡鴉大師，這些鳥兒們安全無虞。)

Visitors are able to see them (a)   the ground, the stairs or high walls. (遊客們才能夠在地上、樓梯或高牆上看見牠們。)

He is the protector (a)   this British tradition. (渡鴉大師是這項英國傳統的守護者。)

Although the job is very difficult and takes (a)   effort, it is a great honor to be a Ravenmaster. (雖然這項工作困難且需要費盡心力，但是擔任渡鴉大師是至高無上的榮耀。)