北京市各植物检疫机构所签发的植物检疫证书编号均为（）位数字编码格式。
A、8
B、12
C、14
D、15
参考答案：D
虚脱
More than a year later he arrived back in America ______.
A．ill, tired and unhappy
B．with ill, tired and unhappy
C．felt ill, tired and unhappy
D．be felt ill, tired and unhappy
