—_________ on historical facts, it's well worth reading.
Hurry up ! The train____ . There is only ten minutes to go.
The hunter insisted that he _____ a tiger and that a searching team ______ to hunt for it.
Ever since my brother graduated from the university, he _______ in the present company for 15 years and he is now chief engineer of the company.
I’d prefer ______ in the office rather than _____ at home watching TV.
Sometimes customers can’t help _____ the things they don’t really need.