题目内容：
根据下面内容，回答题：One British school is finding that allowing children to listen to music or even to have the TV onwhile studying is helping improve grades.21 your teenager starts a family quarrel by sitting in anarmchair listening to music while doing his homework,why not 22 a simple experiment? Ratherthan taking the heavy handed (严厉的) line of ordering him to his bedroom to get on with it 23 ,let him do the homework the 24 he wants. You might well find that his essay is more sparkling(有文采的than 25 he's done before.
According to the research of Millfield prep school, around 20% of yo'tmgsters 26 best withbackground music,10% excel( 突出 )when allowed to break up their work with short walks aroundthe room while up to 80% can concentrate(集中注意力) 27 if allowed to fiddle(用手拨弄 )with a small object.
The research has advised the school to adopt (采取a complete 28 approach (措施, analy-zing pupils to discover which learning style 29 them best--then letting them do their work listen-ing to music or 30 lying down. Doubtful parents at first regarded the move as a layabout's( 懒散 闲荡的人)deed but many are now applying it at 31 where children are also allowed to do their work 32 the television on.
"I 33 to work on the floor with music on low," admits Susan,13,a day-girl(走读女生 )."At first my parents thought I was skiving (逃避 ), but my 34 persuaded them to look at myhomework and when they saw it was OK,they 35 "
第21题应选( ) A．Next time
B．Then
C．Before long
D．In case
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