颈侧1／3折断，折断线在龈下1～4mm时，可采用（）
A.降低咬合
B.正畸牵引术
C.药物脱敏
D.覆盖义齿修复
E.夹板固定
参考答案：B
It is said that a new robot ______ by him in a few days.
A．designed
B．has been designed
C．will be designed
D．will have been designed
提货单、运货单、仓库栈单以及商业汇票都属于商品证券。（）
