It is foolish ______ such a mistake.

单项选择题No sooner had we reached the top of the mountain ______ we all sat down to rest.

单项选择题Neither Mary nor her brother ______ good at singing.

单项选择题I don't think it advisable ______.

单项选择题—______ —Yes, a bit cold, though.

单项选择题—So you missed the meeting. —______. I got there five minutes before it finished.