"There are a piano and a phonograph in the room"

Question

There are a piano and a phonograph in the room

or

There is a piano in the room

I am kind of confused between these two.

Answer 1

You should use is:

There is a piano and [there is] a phonograph[, both of which are] in the room.

However, you should use are in the reverse situation:

The piano and the phonograph are in the room.

Notice how in the first example, there is is applied to the first object, and therefore we can assume that it applies to the following objects unless otherwise specified. We use is because we apply action to object one at a time.

In the latter, we do not specify an action for the first object, opting instead to specify an action for all objects at the end. We must use are because we are grouping all objects.

Hope this helps!