Hello, I can help you to translate. Run as fast as you can. 你能跑多快就跑多快。/尽可能地跑。 Write as much as you can. 你能写多少就写多少。/尽可能地写。 Work as hard as you can. 尽你的可能去努力工作。/尽可能地努力工作。 Hope this is helpful to you.

Run as fast as you can. 奮力的跑 竭力的跑 Write as much as you can. 手不輟筆 手不停揮 Work as hard as you can. 盡瘁 鞠躬盡瘁，死而後已 燃膏繼晷 做牛做馬 夙夜匪懈

（你）能跑多快就跑多快

有多快跑多快。my answer is the most nature way to say the same thing.

I'm trying to ask -- how do you do X as much as you can? ...能....就.... -....as....as..... Run as fast as you can. -能跑多快就跑多快 -Neng Pao Duo Kuai Jiu Pao Duo Kuai. Write as much as you can. -能寫多少就寫多少 -Neng Xie Duo Shao Jiu Xie Duo Shao. Work as hard as you can. -能做多少就做多少 -Neng Zuo Duo Shao Jiu Zuo Duo Shao. CAUTION: Pinyin is only defined the pronunciation of the character, do not try to spell the words by memorize it! Owo)/