SELECT name FROM captain WHERE rank  =  'Midshipman' OR rank  =  'Lieutenant'
What are the names of captains that have either the rank Midshipman or Lieutenant?
[Schema (values) (types)]: | ship_1 |  captain : captain_id (text) , name (number) , ship_id (text) , age (number) , class (text) , rank (text) | Ship : ship_id (text) , name (number) , type (text) , built_year (number) , class (text) , flag (text);