First take 3 litre in 3 litre container and pore it in 5 litre container.

Then again 3 litre in 3 litre container and pore it in 5 litre container, now 1 litre is remaining in 3 litre container.

Now empty the 5 litre container. Then pore the water from 3 litre container to 5 litre.

Then full the 3 litre container and transfer it to 5 litre container. Now 5 litre container contain 4 litre of water