Plaintiff commenced this action seeking damages for injuries he sustained when the vehicle in which he was a passenger left the roadway and struck a tree. The vehicle was operated by defendant, plaintiffs son, and plaintiff was aware that defendant had only a learner’s permit. Within five minutes of leaving the parties’ residence at approximately 6:40 a.m., defendant fell asleep at the wheel. According to plaintiff, defendant’s negligence in operating the vehicle was the sole proximate cause of the injuries sustained by plaintiff. Defendant raised plaintiff s alleged comparative fault as an affirmative defense pursuant to CPLR article 14-A.
As limited by his brief, defendant appeals from the order insofar as it granted that part of plaintiffs motion for partial summaiy judgment on the issue of comparative fault and denied defendant’s cross motion for partial summary judgment on that issue. We conclude that Supreme Court erred in granting that part of the motion with respect to the issue of comparative fault, and we therefore modify the order accordingly.
A licensed driver supervising an unlicensed driver with a learner’s permit owes a duty to use reasonable care as an instructor (see Michalek v Martyna, 48 AD2d 1005 [1975]), and he or she also owes a duty to take necessary measures to prevent negligence on the part of the driver with the learner’s permit (see generally Lazofsky v City of New York, 22 AD2d 858 [1964]). Even assuming, arguendo, that plaintiff established his entitlement to judgment as a matter of law on the issue of comparative fault, we conclude that defendant raised triable issues of fact by submitting evidence that, prior to the accident, plaintiff was preoccupied with reviewing a list on a piece of paper. In addition, plaintiff testified at his deposition that he did not realize that the vehicle was leaving the roadway until he “felt the right tire go off the shoulder,” and he was unable to estimate the speed at which defendant was operating the vehicle. Based upon that evidence, a jury could conclude that plaintiff had breached his duty of care in supervising defendant’s operation of the vehicle and that such culpable conduct diminished plaintiffs recoverable damages (see Pierson v Dayton, 168 AD2d 173, 176 [1991]; Savone v Donges, 122 AD2d 34 [1986]).
We further conclude that defendant raised a triable issue of fact whether plaintiff failed to use reasonable care in his capacity as a passenger. Plaintiff’s “knowledge of the competency, ability, skill and condition of [defendant] and [defendant’s] ap*1613parent awareness of potential dangers” are all factors to be considered by the jury in determining whether plaintiff used reasonable care or was comparatively negligent (PJI 2:87). Here, defendant admitted that he fell asleep at the wheel. We note that a passenger may be “negligent in riding with an obviously sleepy driver” (Purchase v Jeffrey, 33 AD2d 620 [1969]), and we have rejected the notion that “sleep sometimes presses down without warning” (Kilburn v Bush, 223 AD2d 110, 115 [1996] [internal quotation marks omitted]).
All concur except Garni and Lindley, JJ., who concur in the result in the following memorandum.