Ships are but boards, sailors ... These lines ______.
举一反三
- When the people saw the land,（） A: only passengers were glad B: the sailors had to swim ashore C: they were surprised at the news that some ships never arrived D: all of them were excited
- Why does the author mention the Flying Dutchman?___ A: as the basis of primitive navigation systems B: as an example of a commonly sighted phantom ship C: as the reason why many sailors have mental problems D: as an explanation for sightings of phantom ships
- 数据库中SAILORS表是由joe创建的.在DBMS完成下面的语句后Grant select on Sailors To Art With Grant option...Joe执行Grant select,update on Sailors To Bob With Grant option...Joe执行Grant select on Sailors To Bob With Grant option...Art执行Revoke select on Sailors From Art Cascade...Joe执行Bob对Sailors表拥有[1分]
- 关系模式Sailors(sid,lastname.firtname,age,ratring)，其中lastname允许为空. 下面哪个语句能够查找出lastname属性值不为空的水手信息. A: SELECT * FROM SAILORS WHERE LASTNAME<>’NULL’ B: SELECT * FROM SAILORS WHERE LASTNAME<>NULL C: SELECT * FROM SAILORS WHERE LASTNAME IS not NULL D: SELECT * FROM SAILORS WHERE LASTNAME not LIKE ’NULL’
- Which of the following lines are used as dimension lines， extension lines， leader lines， construction lines， section lines and projection lines？（ ） A: Thin phantom lines B: Thin solid lines C: Thin center lines D: Wavy lines