keep one's eyes open

Idioms  

1. Also,. Be watchful and observant. For example, We should keep our eyes open for a change in the wind's direction, or Keep your eyes peeled for the teacher. The first phrase dates from the late 1800s; the second and third, both colloquial and alluding to the lids not covering the eyes, date from the mid-1800s and 1830s, respectively.

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Example Sentences

There’s any amount of real misery to be met with in the neighbourhood of the Docks, ay, and all over London, for that matter, if one only chooses to keep one’s eyes open.

From The Pirate Island A Story of the South Pacific by Staniland, C.J.

I tell you one had to keep one's eyes open in those days.

From Captain Bayley's Heir: A Tale of the Gold Fields of California by Paget, H. M. (Henry Marriott)

Of course, it was needful to exercise a certain amount of discretion, to keep one's eyes open whilst in the water; and I do not say that there was no danger present.

From Treasure of Kings Being the Story of the Discovery of the \"Big Fish,\" or the Quest of the Greater Treasure of the Incas of Peru. by Gilson, Charles

“A very good school, I should say, Embleton; one has to keep one’s eyes open there.”

From With Cochrane the Dauntless by Henty, G. A. (George Alfred)

One cannot keep one's eyes open very long without winking, but the stranger never winked at all.

From The Best British Short Stories of 1922 by Cournos, John