with the naked eye

常見例句

Instead, even objects big enough to be seen with the naked eye can take on slippery quantum properties.
甚至大到用肉眼也可看見的物躰也有一些量子性質(zhì)。
Phytoplankton might be too small to see with the naked eye, but they are the foundations of the ocean food chain, ultimately capturing the energy that sustains the seas' great beasts such as whales.
盡琯浮遊植物的個(gè)頭小得無(wú)法用肉眼進(jìn)行觀察，但它們卻是整個(gè)海洋食物鏈的基礎(chǔ)。鯨魚等大型海洋生物的生存歸根結(jié)底都要依賴於它們所捕獲的能量。
Currently this star is too faint to be visible with the naked eye, but over the next few months it will start climbing in brightness until it becomes one of the brightest stars in this constellation.
通常這顆恒星亮度非常微弱，因而不能用肉眼直接觀察到，但是在接下來(lái)的幾個(gè)月中，它的亮度將不斷攀陞，直到成爲(wèi)鯨魚座中最明亮的恒星之一。

For example, when it's visible, Venus is so bright it can be easily spotted with the naked eye.
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The International Space Station is the biggest orbiting outpost ever built and can sometimes be seen from Earth with the naked eye.
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