There is a drop of blood on your collar. What happened?

你的领子上有一滴血。发生了什么事？

youdao

He'll also drop in on a tech company and talk with blue-collar workers.

NPR: Obama To Launch Series Of Trips On Economic Plans

Now, it's true that not long ago, you could drop out of high school and reasonably expect to find a blue-collar job that would pay the bills and help support your family.

WHITEHOUSE: Helping America Become a ��Grad Nation��