yī yǎn
a glance
a quick look
a glimpse
yī yǎn wàng qù
as far as the eye can see
yī bǎn yī yǎn
lit. one strong beat and one weak beats in a measure of music (two beats in the bar) (idiom); fig. follow a prescribed pattern to the letter
scrupulous attention to detail
yī yǎn kàn chuān
to see through something at first glance (idiom)