Mr Black decided to give up his farm and devote all his time to______ those children living on the streets.

A．help

B．helping

C．be helping

D．being helped

吞咽障碍评定的意义有（）

A.筛查吞咽障碍

B.提供吞咽障碍病因和解剖生理变化的依据

C.确定患者误咽的危险因素

D.确定需要改变提供营养的手段

E.为吞咽障碍诊断和治疗推荐辅助测试及必要程序