阅读短文，从方框中选择恰当的词并用其适当形式填空，使短文完整、通顺．每词限用一次，其中有两个是多余的．

easy，message，good，start，divide，if，they，safe，excite，avoid，problem，sit

The new year brought new desks for students at a school in California，USA．The school's classrooms have all changed（1）

their

their

seated desks to standing desks．"It's now the first all-standing school，"Juliet Starrett says．She（2）

started

started

the group StandUp Kids and wanted to have every US public school kid using a standing desk in the next 10 years．
Starrett's daughters are both at that school．They are（3）

excited

excited

about their desks．"You feel happier，you're less tired and you're more active，"one of the girls says．
Some of the desks have wheels．Wheels allow the desks to be moved（4）

easily

easily

．The desks are also able to be set at different heights．Kids take breaks by（5）

sitting

sitting

on the floor or on stools （凳子）．
Mark Benden is an expert who studies how to make things easy and（6）

safe

safe

to use．According to him，standing workers are more focused （注意力集中的） and healthier．Researchers in New Zealand，Australia and the United Kingdom had similar findings．
But not everyone believes standing is（7）

better

better

than sitting．Some parents and teachers worry that kids will get tired and that standing for long may cause（8）

problems

problems

．And standing desks are more expensive．
Benden says both sitting and standing desks can cause problems（9）

if

if

they are not the proper height．"Our（10）

message

message

should not be'Sit less，stand more'，"he says，"but'Sit less，move more'．"