adjective - working secretly, especially as a police officer trying to get information without people knowing who you really are
noun - the place where a crime happened and where the police look for clues and evidence
adjective - having a speckled appearance of light and dark colours mixed together
adjective - having a mixture of dark and white or grey hairs
noun - an unpleasant, harsh, or metallic ringing sound made by metal objects hitting each other
verb - to make a harsh, discordant, metallic sound, or to cause something to make such a sound
adjective - describing petrol that contains lead compounds
adjective - describing petrol that does not contain lead, which is less harmful to the environment and engines
noun, British English - a list of people showing when they are on duty, working, or taking part in an activity
noun - a list of members of a team, group, or organization
noun - a list of people showing when they are on duty, working, or taking part in an activity
noun - the ability to imagine or plan what will or might happen in the future and to prepare for it wisely