过去是一种始终存在的阴影，无论你选择忽视与否。
The past is a kind of shadow which is always there, whether you choose to ignore it or not.
The ethical questions raised by CRISPR are not obstacles—they are essential conversations.
生活是一场冒险，每一个挑战都是成长的机会。
A teacher must have a healthy body, the skills of a farmer, the mind of a scientist, the interest in art, and the spirit of social reform.
科学在开放和合作的环境中蓬勃发展。
I don't rap for dead presidents. I'd rather see the president dead.