焊接热影响区即是指焊接时焊缝两侧受热的区域。
参考答案:错
--Why has he been staying at home these days?
--He ___________ since a month ago.
A.has been out of work
B.was out of work
C.has lost his work
D.had left from his work
依法必须进行招标的项目,招标人应当自确定中标人之日起( )内,向有关行政监督部门提交招标投标情况的书面报告。
A.7日 B.10日 C.15日 D.20日