v.使…成为必要，需要( necessitate的过去式和过去分词 )...

Frank was carrying out fuel-system tests which necessitated turning the booster pumps off.弗兰克在做燃料系统测试，这一测试需要关掉升压泵。A prolonged drought had necessitated the introduction of water rationing.由于持续干旱，用水需要实行配给了。The word " neces...

A prolonged drought had necessitated the introduction of water rationing...由于持续干旱，用水需要实行配给了。A prolonged drought had necessitated the introduction of water rationing.由于持续干旱，用水需要实行配给了。Frank was carrying out fuel-system tes...

necessitated的音标：...