http://w3n-a.blogspot.com/2008/12/re...of-stalls.html

Pilots must recognize the flight conditions that are conducive to
stalls and know how to apply the necessary corrective action. They
should learn to recognize an approaching stall by sight, sound, and
feel. The following cues may be useful in recognizing the approaching
stall.

Several types of stall warning indicators have been developed to warn
pilots of an approaching stall. The use of such indicators is valuable
and desirable, but the reason for practicing stalls is to learn to
recognize stalls without the benefit of warning devices.

http://w3n-a.blogspot.com/2008/12/re...of-stalls.html