Beijing (CNN)Much of the Chinese capital shut down Tuesday after Beijing's city government issued its first red alert for pollution, closing schools and construction sites and restricting the number of cars on the road.
In the sentence above, it's used as an intransitive verb.
If you're not sure what (to) shut down means, read the following subheading:
Children kept at home, building sites and factories closed and cars kept off roads as pollution engulfs Chinese capital
It can also be used as a transitive verb:
This common two-word verb is also used as a noun!
It seems like Congress is always threatening a shutdown, such as this one:
If you look online, you can see how often members of Congress threatens a shutdown if they don't get what they want. How many recent threats of a shutdown can you find? Here's one more, to get you started:
And by the way, not only politicians threaten shutdowns. Anybody can get into the act. Taxi drivers and truckers can do it too, as we see here:
Fortunately they were unsuccessful.