a. Concrete door.
Door Concrete have the power of sturdy. Generally, making of concrete door entangle expert maker of this door. On the score of expense of its very is costly levying, not many farmer using [it]. Levying of concrete door [is] usually performed [a] by local local government to be used by many farmer of prawn [in] coast. Besides, consumer of this door that is big company which [do/conduct] prawn conducting intensively.
Source : S. Rachmatun Suyanto and Ahmad Mujiman, 1999.
