白天的时候，白天
when it is naturally light
I prefer travelling by day. 我喜欢白天旅行。
By day, this stretch of the road is incredibly busy.
By day, the streets are jammed with workers, but they all clear out after 5.00 p.m.
By day, this quiet shopfront is a bookshop. By night, it's the city's hottest new nightclub.
We spent two fantastic weeks there, walking by day and sampling the region's cuisine in the evening.
See also: day