31.
(A) Designers must then consider the space available for the coaster.
(B) Building an exciting roller coaster starts with a brilliant design.
(C) Theme and type are also important aspects to consider in coaster design.
(D) Designers can draw on a number of techniques to provide a memorable ride.
(E) When the design is complete, detailed calculation and careful testing procedures will follow.

31. 選項：(B) Buildin...