各级税务机关应当对其工作人员执行法律、行政法规和廉洁自律准则的情况进行监督检查。
参考答案：对
—Has your father returned from Europe yet?
—Yes, but he ______ here for only three days before his company sent him to America.
A．was
B．has been
C．will be
D．would be
Michael Jordan is a man who never gives up in his life. And that's _________ he succeeds．
A．what
B．when
C．why
D．where
