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I didn't know about some of them, thank you:)

It's normal to use "the roads are busy", or "there's a lot of traffic today". It's normal to use "traffic jams", but a little bit long-winded for everyday speech. Instead of "busy", you might use "packed", or "crowded", or even "the traffic is slow today", or "there's a lot of traffic today" ... so many choices :)

Moved

Thank you Michael!