Williams Formula 1 driver Robert Kubica says he still needs consistent behaviour from his car to turn around what has proved to be a "complicated" 2019 season.
Back on the grid this year having missed eight F1 campaigns following his devastating early-2011 rally crash, Kubica has struggled to match team-mate George Russell in most of the races held so far.
Asked by Autosport to describe the first half of the season, Kubica said: "Complicated, it has been complicated. Overall there are a few things that we have to get on top of apart from the performance of the car.
"I think once we fix them or we have more consistency it will be much easier so hopefully the second part of the year we'll get on top of it and then at least we'll be able to have consistent performance every weekend which will be much easier.
"You can always improve everywhere but, as I said, we have to have consistency.
"Once you have consistency in the car it will also be much easier from the driver point of view to be consistent and to work on small details and this is in the end what it comes down to in F1."
Russell put on Williams's strongest performance of the year so far at the Hungarian Grand Prix, the final race before the summer break.
He was 16th fastest in qualifying, ahead of both Racing Points and Daniel Ricciardo's Renault as well as Kubica, then beat Lance Stroll's Racing Point and Antonio Giovinazzi's Alfa Romeo to finish 16th on race day.
But Kubica believes it is too early to tell if Williams has made an actual step forward.
"We have to wait and see," said Kubica, whose 10th place in Germany after the Alfas were penalised is Williams's only point of 2019 so far.
"For sure George had a much better performance but the car was the same as in Hockenheim and in Hockenheim it was not looking like we made big progress.
"Putting it in a different way, we made progress but also the others did so the gap was still big.
"He managed to qualify in front of a few cars and he was much closer to the pack.
"We hope we will be able to continue with this trend although it will require a lot of work.
"After the break we have completely different tracks so we have wait and see if we'll be able to close the gap and stay more attached to the others as George was."
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