一些微生物是肉眼看不见的。
Some microorganisms are invisible to ___the ___naked ___eye.
在晴朗的夜晚,金星用肉眼清晰可见。
The planet Venus is clearly visible with ___the ___naked ___eye on a clear night.
没有显微镜,细菌无法用肉眼观察。
Without a microscope, bacteria cannot be observed by ___the ___naked ___eye.