to use up, empty, (supplies etc) until little or none remains
consume, exhaust supply
to look at (a person, thing) carefully in order to learn something; to put questions to (a person) in order to test knowledge or get information
analyse, test
to travel into or through (a country etc) for the purpose of learning about it
investigate; survey
to go to or near (a place or area occupied by enemy forces) to learn about their position, strength etc
investigate; survey
to put (something), separate (something) by putting, through a sieve; to examine something carefully
take out residue; remove impurities