I can give you several sentences.That leather will stiffen if you let it get wet.I felt him stiffen in shock as he saw the boss walk in unexpectedly.You can stiffen lace by adding starch.
I/you/we/they stiffen. He/she/it stiffens.
Loosen up is the opposite of stiffen up.
Use a heavier weight
lack of potassium
they clean the insides of the body then they use this pacific kind of liquid to stiffen the body and rap cloth around the body.
set, solidify, stiffen, :)
stiff
the molecues stiffen up
Yes it normal for infants to stiffen when crying or screaming. It is caused by the action of crying (try screaming really loud and you will find that you tense your body), they also stiffen if they do not want to be picked up. As long as the stiffness does not last beyond the crying there is nothing to worry about.
To stiffen the floor frame.
My upholstery man uses hair spray.