单项选择题

What is TRUE of human sleep

A．Most people need less sleep when grown older.
B．Most people need seven and a half hours of sleep every night.
C．On average, people in the US today sleep less per night than they used to.
D．Most people need more sleep when they are under pressure.

<上一题目录下一题>

热门试题

单项选择题

Sleep defensively means that people should ______.

A．go to see a doctor when they have sleep problems
B．keep to a flexible sleep pattern
C．sacrifice other things to get enough sleep if necessary
D．follow changeable sleep routines

单项选择题

From what the Brazilian biologist says, we know that tourists like her ______.

A．are reluctant to carry cash with them
B．simply don't care how much they spend
C．are not good at planning their expenditure
D．often spend more money than they can afford