The children are all fourth-graders at a Washington-area elementary school.
VOA: special.2009.12.21
The clinical trial was designed such that almost two million elementary school children were given this test vaccine.
该临床试验的计划是,向近二百万的小学学生,接种这种测试疫苗
They did this in 1,800 elementary school children, so these are about eight year-olds.
于是科研人员给一千八百名,八岁左右的小学生分发疫苗
"It's recommended that children get 150 minutes of exercise a week at elementary school and 225 minutes in secondary schools and yet they are not.
VOA: standard.2010.03.09
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