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

A man had to know the surroundings well to find his way now; one had to feel — it was impossible to keep one's eyes open.

From The South Pole; an account of the Norwegian antarctic expedition in the "Fram," 1910-1912 — Volume 1 by Chater, Arthur G.

One has only to keep one's eyes open in passing the streets to become aware of the physical deterioration of thousands of the wage-earners.

From The Cost of Shelter by Richards, Ellen H.

It is best to be serious and cautious, and to keep one’s eyes open, when one travels that way.

From Ainslee's, Vol. 15, No. 6, July 1905 by Various

A man had to know the surroundings well to find his way now; one had to feel -- it was impossible to keep one's eyes open.

From The South Pole; an account of the Norwegian Antarctic expedition in the "Fram," 1910-12 — Volume 1 and Volume 2 by Chater, Arthur G.

One had to keep one's eyes open there, for they were every bit as brave as we were.

From On the Pampas by Henty, G. A. (George Alfred)