单项选择题
After being rescued from the vessel accident，the people agreed that they had much to（）.
A.thank B.be thankful C.be thanked D.be thankful for
单项选择题 After being launched from a vessel，totally enclosed survival craft which have been afloat over a long period require（）.
单项选择题 Admiralty EasyTide（）.
单项选择题 Aboard a survival craft，ether can be used to（）.
