Roy trenton drove a taxi before.A short while ago,however,he

Roy Trenton used to drive a taxi.A short while ago,however,he became a bus driver and he has not regretted it.He is finding his new work far more exciting.
这句句中为什么用了现在完成时

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Roy Trenton used to drive a taxi.A short while ago,however,he became a bus driver and he has not regretted it.He is finding his new work far more exciting.When he was driving along Catford Street recently,he saw two thieves rush out of a shop and run towards a waiting car.One of them was carrying a bag full of money.Roy acted quickly and drove the bus straight at the thieves.The one with the money got such a fright that he dropped the bag.As the thieves were trying to get away in their car,Roy drove his bus into the back of it.While the battered car was moving away,Roy stopped his bus and telephoned the police.The thieves' car was badly damaged and easy to recognize.Shortly afterwards,the police stopped the car and both men were arrested.
where they running out of a shop,or were they running out of a bank?where did Roy drive his bus?Did they drop the stolen money or not?Did they get into a car,or did they run away?(and...so...and)

Roy Trenton used to drive a taxi.A short while ago,however,he became a bus driver and he has not regretted it.He is finding his new work far more exciting.When he was driving along Catford Street recently,he saw two thieves rush out of a shop and run towards a waiting car.One of them was carrying a bag full of money.Roy acted quickly and drove the bus straight at the thieves.The one with the money got such a fright that he dropped the bag.As the thieves were trying to get away in their car,Roy drove his bus into the back of it.While the battered car was moving away,Roy stopped his bus and telephoned the police.The thieves' car was badly damaged and easy to recognize.Shortly afterwards,the police stopped the car and both men were arrested.当中的He is finding his new work far more exciting.为什么要用现在进行时?

英语翻译
The Trenton Bath House is derived from a concept of space order in which the hollow columns supporting the pyramidal roof distinguish the spaces that serve from those being served.