The form bifocal is used as a modifier. bifocal 用作修饰语。
N-PLURAL 双光眼镜;远近两用眼镜 Bifocals are glasses with lenses made in two halves. The top part is for looking at things some distance away, and the bottom part is for reading and looking at things that are close.
双光眼镜;远近两用眼镜 View usage for:All yearsLast 10 yearsLast 50 yearsLast 100 yearsLast 300 years