. ---- How long ____ at this job?

---- Since 1990.

A．were you employed

B．have you been employed

C．had you been employed

D．will you be employed

半侧脊髓病变出现病变水平以下

A．同侧运动、痛温觉障碍，对侧深感觉障碍

B．对侧运动、痛温觉障碍，同侧深感觉障碍

C．同侧运动、深感觉障碍，对侧痛温觉障碍

D．同侧运动、对侧深浅感觉障碍

E．同侧运动、痛温觉和深感觉障碍