The conclusion is（）the said ship is fit to continue to sail. ["it","this","that","what"]
简述纤毛虫病。
在地址栏输入一个WWW地址后，浏览器中出现的第一页被称为（）。 ["导航","主页","网页","网站"]
In a hydraulic system, （） are used to protect the system from over pressure. ["stop valves","check valves","safety valves","reducing valve"]
The burden of proving unseaworthiness is upon those who（）it. ["approves","alleges","allows","permit"]
简述怎样测量炉顶空间温度？
