Republicans had become stronger since the last presidential election in eighteen fifty-six.

VOA: special.2009.07.09

It's simply your psychological immune system will become stronger, hopefully already by the end of this semester.

只是你的心理免疫系统会变得更强，希望在本学期未就见成效。

哈佛公开课 - 幸福课课程节选

Psychological immune system will become stronger.

心理免疫系统会变得更强。

哈佛公开课 - 幸福课课程节选

I want my country to become stronger."

VOA: standard.2010.02.14