normal space

例句：

1. 1. The normal space for thistask is 500 words.
   完成这项任务的正常空间是500字。
2. 2.The normal space for the data is withinthe range of 10 to20 percent.
   数据的正常范围是10%到20%。
3. 3. The normal space fora human body is about 7 feetin height.
   人体正常的空间高度约为7英尺。