Many of you will have been caught in this scenario yourself.
You can see the car starting to change lanes, but what can you do to stop it?
This young motorist was so sure that the coast was clear in this dashcam clip, first posted on the Facebook page DashCamOwnersAustralia, they even put the indicator on before moving left from the centre lane.
The truckie said that thankfully the young 17-year-old driver was okay after the accident near Muir Road, Chullora, in west Sydney.