A shudder shook the boy's frame, and his face blenched.

男孩打了个寒颤，脸色也变白了。

She blenched before her accuser.

她在(她的)指控者面前畏缩了。

She blenched before her accuser.

她在指控者面前畏缩了。

She blenched at the thought of picking up the dead animal.

在想到拾起动物尸体时她退缩了。