Reply to "Articles"

to take a bus
to take the bus

With most modern means of public transportation we usually use "the":

I usually take the bus to work, by today I walked

If the means of transportation is viewed as distinctive, we use "a":

You can get almost all the way to the airport on the subway now, but at the end of the line you have to take a bus ("take a different means of transportation")

to take a taxi
to take the taxi

Taxis are not considered public transportation; you take a (not *the) taxi

to go to a park
to go to the park

Places and institutions such as parks, beaches, supermarkets, banks, and libraries, which are considered a familiar part of the environment that one lives in, use "the." The definite article "the" does not refer to a specific place; it refers to the kind of place, implying that that type of place will be well known to the hearer. We say

I usually take my dog to the park for his walk, but today was so sunny that we went to the beach

My grandfather used to live in the mountains

They have a house right on the ocean

You can find that book at the library or the supermarket

"The" indicated shared information.

The indefinite article "a" is similar but it does not imply that the place is a familiar location or institution. It refers to "any member of the class" and indicates "new" information:

When I visited my cousins we went to a park for an outdoor concert

You can find that book at a library or a supermarket

Marilyn Martin