non-rigid       
adjective (also nonrigid) uk/ˌnɒnˈrɪdʒ.ɪd/ us/ˌnɑːnˈrɪdʒ.ɪd/
 柔软的,可弯折的
able to be bent or moved; not stiff or fixed
  These airships have non-rigid frames.
 Most of the manufacturers sell their products in nonrigid bags. 大多数制造商都把他们的产品放在软质袋子里出售。 
 - More examples
 - The army and navy prefer to use non-rigid air-ships.
 - The robots were able to fold nonrigid items such as towels into fixed shapes.
 - Handling non-rigid materials is difficult, because their flexibility lets them take on different shapes.
 - Non-rigid airships were able to remain in the sky for many hours and send down reports by wireless.