什么是 maintain?To keep up or carry on; continue: maintain good relations. To keep in an existing state; preserve or retain: maintain one's composure. To keep in a condition of good repair or efficiency: maintain two cars. To provide for; support: maintain a family. To keep in existence; sustain: enough food to maintain life. To defend or hold against criticism or attack: maintained his stand on taxes. To declare to be true; affirm: maintained her innocence. To adhere or conform to; keep: maintain a busy schedule.