<prompt> Pedzisa mutsara unotevera: Ferrari 643 yaiva Formula One motokari yakagadzirwa naSteve Nichols naJean-Claude Migeot uye yakavakwa naScuderia Ferrari kuti ishandiswe mu 1991 Formula One mwaka. Yakagadzirwa mukati meMay uye yakatangwa pa  <response>: French Grand Prix pakutanga yairatidzika kuva ine bviro yokumhanya pamberi. Alain Prost akakwanisa mumutsara wokutanga uye akatungamirira, uye kunyange zvazvo akazopedzisira apfuurwa naNigel Mansell muRenault powered Williams FW14 yake, nzvimbo yechipiri mumutambo wokutanga wemotokari yacho yakaratidza kuvimbisa. Kunze kwokuva nguva dzose pamberi pechikwata, zvisinei, kwakanga kusingafaniri kudaro. 