Main entry: control, assure, ascertain, insure, check, ensure, see, see to it
Definition: be careful or certain to do something; make certain of something
Usage: He verified that the valves were closed; See that the curtains are closed; control the quality of the product
Main entry: ascertain
Definition: learn or discover with certainty
Main entry: ascertain, find, find out, determine
Definition: establish after a calculation, investigation, experiment, survey, or study
Usage: find the product of two numbers; The physicist who found the elusive particle won the Nobel Prize
Main entry: see, learn, determine, ascertain, check, watch, find out
Definition: find out, learn, or determine with certainty, usually by making an inquiry or other effort
Usage: I want to see whether she speaks French; See whether it works; find out if he speaks Russian; Check whether the train leaves on time