岩层的褶皱构造中,岩层向下拱起的弯曲称为背斜褶曲;岩层向下凹的弯曲为向斜褶曲。( )
参考答案:错
I have been advised to arrange for insurance _________ I need medical treatment.
A.so that
B.unless
C.in case
D.though
在Excel 中,A1 单元格的值为18,在A2 单元格中输入公式“=IF(A1>20,"优",IF(A1>10,"良","差"))”,按回车键后,A2 单元格中显示的值为 (56) 。
A.优
B.良
C.差
D.#NAME?