【单选题】正常人体内环境的理化特性经常保持的状态是
【单选题】The word 'lacto-vegetarian' in Paragraph 4 means
A.
very strict vegetarian
【单选题】If you are a vegetarian ()
A.
there will be no problem
B.
you will have to pay extra
C.
you must notify Amazing Tours in advance
D.
you must bring your own ingredients
【单选题】DNS客户向本机所配DNS服务器发出的查询和DNS服务器向其它DNS服务器发出的查询分别是()。