Since they only sleep in/at/for/during a little bit at a time,

问题描述:

Since they only sleep in/at/for/during a little bit at a time,
the term "light sleeping" is used to describe their (behaviour/heart/body/habits).
选择并翻译,最好说明为什么

habits
这个“开灯睡觉”通常用来描述他们的习惯
for
因为他们一次只是小睡一会