基本上可以,但错误也不少,稍微帮你改改.
1. She must have left very early for she didn't show up during the breakfast time.这句是对已完成的是的推测,所以用must have done格式,另外,because语句不能和主句分开,所以要用逗号.
2. Too much work and too little rest often leads to illness.主语要明确.
3. He responds to my advice with a smile. with a simle习惯用法.
4. I always regrets buying the farm.这句注意,regret doing是为做过的事遗憾,而regret to do是为要做的是遗憾.