A:ability
B:force
C:strength
D:mind
四冲程内燃机有四个工作冲程:吸气冲程、压缩冲程、做功冲程、排气冲程,其中将内能转化为机械能的是____ 冲程。
从上面看到的形状是哪个图形?( )
—I usually share them my classmates and talk about the stories each other.