sample dot

例句：

1. 1. The researchers collected samples from different locations to study the effects of pollution on wildlife.
   研究人员从不同地点收集样本，研究污染对野生动物的影响。
2. 2.During the experiment, we used a sample dot to mark the exact location of the data points.
   在实验中，我们使用一个样本点来标记数据点的确切位置。
3. 3.The scientist noticed that the sample dot was slightly off from the expected value.
   科学家注意到样本点与预期值略有偏差。