Children usually transfer to secondary school at 11 or 12.

儿童通常在11或12岁时升读中学。

《牛津词典》

It does this by matching main trial identifiers to secondary trial identifiers found in trial records.

其通过将试验主要标识符与试验记录中找到的试验次要标识符匹配，从而完成这一尝试。

youdao

Rather, HIV, the virus that causes it, weakens the body's immune system and exposes the sufferer to secondary infections.

由HIV病毒引起的艾滋病先是导致了病人免疫系统功能减弱，继而使病人产生继发感染。

youdao

When the disease changes to Secondary Progressive, the disease begins to grow worse.

VOA: special.2009.01.06

This is an unfortunate thing you see throughout education frankly, certainly at the secondary and primary school level where you just insert technology into the classroom and expect to solve problems, that is not in life always the case.

遗憾的是,中小学教育中,就是讲知识然后运用所学的知识解决问题,但是实际生活中不总是这样。

哈佛公开课 - 计算机科学课程节选

So, every time you're exposed to a new vaccine or a new antigen you go through this primary response before you have the secondary response.

所以,每当你接触到新疫苗或是新抗原,在再次免疫之前,机体将会经历这样的初次免疫过程

耶鲁公开课 - 生物医学工程探索课程节选

Saxony kept the selective element, but sent pupils to secondary school at 13 rather than 11.

ECONOMIST: Reforming education

The differences, though, that the way vice presidents are used, usually they're sent to secondary markets.

NPR: After Conventions, McCain Takes Lead In Some Polls

Most critically, many primary school children failed to proceed to secondary level due to financial constraints.

UNESCO: Family Basic Education (FABE)