斗棋结构中斗类构件，细分为坐斗与升。只承受一面的棋或枋，只开一面口(顺身上)，叫做升；承受相交的棋、昂，开十字口，叫做斗。( )
参考答案：对
It is this kind of exciting trip _____most of my classmates only dream about.
A．when
B．while
C．as
D．that
腈纶的弹性比氨纶好，所以用来做弹力纱。
