如图所示,人重G人=600 N,平板重G板=400 N,如果人要拉住木板,他必须用力F=____N,此时人对平板的压力F压=____N。(滑轮重及摩擦均不计)
250;350
不符合Crohn病的描述是().
A.只累及回肠
B.呈节段性分布
C.常呈慢性经过
D.肠黏膜呈鹅卵石状外观
E.形成裂隙及匐行性溃疡
You _____ down everything I said! You can find it on this sheet I’m handing out.
A.shouldn’t have taken
B.must not have taken
C.cannot have taken
D.needn’t have taken