What do these two parts of the lift do
sides of the bone
boobs
A lift
Unless you get very radical and depending on the type of lift, no, you will not need to extend the shaft, they can self extend by themselves.
yes
the yolk is attached to the drive shaft by a universal joint. It slides into the transmission and allows the shaft in the trans to engage the drive shaft
The shaft locks when power not applied.
To lift it by when moving it.
To lift things.
the function of a tail is to lift its body and to increase the speed of flight
To create lift and flight direction.