Complex sentence: In the 2016 season, Vettel had no wins with Ferrari and finished 4th in the standings; but in 2017 with 11 races done, he has 4 wins to his name and he's leading the championship by 14 points over Lewis Hamilton.
Split into simpler sentences: In the 2016 season, Vettel had no wins with Ferrari and finished 4th in the standings. However, in 2017, with 11 races completed, he has 4 wins to his name and is leading the championship by 14 points over Lewis Hamilton.