B
A new study shows that meeting three standards can help kids have stronger brains(大脑). The standards are getting nine to eleven hours of sleep each night,undertaking(从事)at least 60 minutes of physical(身体的)activity a day,and spending less than two hours of screen time a day.
The study came out on 27th September in the *Lancet Child & Adolescent Health*. It examined the habits of more than 4 500 children aged between 8 and 11 in the United States. The study found that 29% of the children met none of these standards,while 41% met only one. About 25% met two and just 5% met all the three standards.
The kids were given tests to check their memory,attention,language skills and planning. Children who met all the three standards scored highest,and they had the best cognition(Cognition means how we learn and understand things). What's more,the more standards the children met,the better their cognitive abilities were.
The researchers(研究人员)wrote that their findings especially showed the importance of restricting screen time and having healthy sleep.
“We found that more than two hours of screen time in children led to poorer cognition. More research into the relationship between screen time and cognition is now needed,including studying the influence of different types of screen time,and whether the programme is educational or not.”
(
C
)4. Which is TRUE about the study?
A. About 25% of the children met only one standard.
B. Most children didn't meet any of the three standards.
C. More than 220 children met all the three standards.
D. Those who met two standards had the best cognitive abilities.
(
D
)5. The underlined word “restricting” means “______”.
A. avoiding B. wasting C. improving D. limiting
(
B
)6. The researchers might continue to examine ______.
A. how healthy sleep improves cognition
B. how screen time influences cognition
C. how many hours' sleep kids need every night
D. how many kids like watching educational programmes
