根据括号内的汉语提示，完成句子。(每空一词)
The young man found it difficult to have dinner because some of his ____ (牙齿)had been pulled out.
Tom and Linda have been____ ( 结婚) for ten years, but they've never quarreled.
If you want to become a good Marathon athlete, you must practice ____ (跑步) every day.
He manages over 100 big companies, He is considered to be one of the most ____ (成功的) businessmen in China.
Their answers to the question were not the same, that's to say, they answered the question____ (不同地).
When you communicate with your American e-pal on the internet, the e-mails are supposed to be____ (写) in English.

朱——____——____   台——____——____

骨——____——____   昔——____——____

①如图1所示，先将沙和沙桶通过滑轮悬挂于小车一端，调节平板的倾角θ，使小车沿斜面向下做匀速直线运动，测出沙和沙桶的总质量m；

②保持平板倾角θ不变，去掉沙和沙桶，小车即在平板上沿斜面向下做匀加速直线运动，通过纸带测量其加速度a；

③保持小车质量M不变，多次改变沙和沙桶的总质量m，每次重复①②两步操作，得到小车加速度与合力的关系；

④多次改变小车的质量，进行适当的操作，得到小车加速度和质量的关系．