Learn Hardcore Serbian: Danas je veliki saobraćaj u centru, pa autobus ide sporije nego obično. - Today there is heavy traffic in the center, so the bus is going more slowly than usual.

Breakdown of Danas je veliki saobraćaj u centru, pa autobus ide sporije nego obično.

Why is je right after Danas?

Because je is a clitic in Serbian. Clitics are short unstressed words that usually go in the second position of the sentence or clause.

So:

Serbian word order is more flexible than English, but clitic placement is one of the big things that still has rules.

You can also move other parts around, for example:

But je still tries to stay in that early clitic position.

Why does Serbian say je veliki saobraćaj instead of something like there is heavy traffic?

Serbian often uses to be where English uses there is / there are.

So:

Danas je veliki saobraćaj u centru
literally looks like Today is big traffic in the center
but naturally it means There is heavy traffic downtown/in the city center today

This is normal Serbian structure. English needs there is, but Serbian often does not.

What exactly does veliki saobraćaj mean here?