"by day" in Chinese (Simplified)
白天
Definition
“By day”指的是白天，与晚上相对。通常用来描述白天发生的活动或状态。
Usage Notes (Chinese (Simplified))
“By day”较为正式或书面，多用于描述两种不同场合（如“白天是XX，晚上是XX”）。与“during the day”不同，“by day”强调与夜晚的对比。
Examples
Many animals hunt by day and sleep at night.
许多动物**白天**捕食，晚上睡觉。
The shop is open by day but closed at night.
商店**白天**营业，晚上关门。
Some people work by day and study at night.
有些人**白天**工作，晚上学习。
He's a teacher by day, but a rock musician by night.
他**白天**是老师，晚上是摇滚乐手。
The city looks peaceful by day, but it's full of life at night.
这座城市**白天**看起来很安静，晚上却充满活力。
The museum offers guided tours by day only.
博物馆只在**白天**提供导览服务。