maintain

assert, affirm, allege, maintain, testify, claim

maintain, conserve, preserve, save, store

动词 maintain:

1. keep in a certain state, position, or activity; e.g., "keep clean"
   同义词：keep, hold
2. keep in safety and protect from harm, decay, loss, or destruction
   同义词：conserve, preserve, keep up
3. supply with necessities and support
   同义词：sustain, keep
4. state categorically
   同义词：assert, asseverate
5. have and exercise
   同义词：wield, exert
6. maintain for use and service
   同义词：keep
7. maintain by writing regular records
   同义词：keep
8. state or assert
   同义词：defend
9. support against an opponent
   同义词：uphold
10. observe correctly or closely
    同义词：observe, keep

1. Mankind have been trying every means to maintain the balance of nature.
   人类采用一切手段保持生态平衡。
2. We must maintain a firm attitude.
   我们必须采取坚定的态度。
3. The government has taken a measure to maintain the stability of prices.
   政府已经采取了措施以确保物价稳定。
4. Mindful of the need to maintain efficient communication, the board of directors decided to construct a new communication network.
   董事会注意到维持有效通讯的需要，因此决定建立一个新的通信网。
5. In order to maintain physical well being, a person should eat wholesome food and get sufficient exercise.
   为了维持身体健康，一个人应该吃有益健康的食品，并经常锻炼身体。
6. The car has to be constantly maintained.
   汽车必须经常保养。
7. He is too poor to maintain his family.
   他太穷了，无法养活家人。
8. Part of my job is to maintain good relationship with our suppliers.
   我的部分工作是同我们的供应商保持良好的关系。

main.tain

v.tr.（及物动词）
main.tained,main.tain.ing,main.tains
To keep up or carry on; continue:
维持或保持；继续：
例句：
maintain good relations.
维持良好的关系

To keep in an existing state; preserve or retain:
保持存在的状态；坚持或保持：
例句：
maintain one`s composure.
保持冷静

To keep in a condition of good repair or efficiency:
保养：使…保持在良好的修缮和效率状态中：
例句：
maintain two cars.
保养两辆小汽车

To provide for; support:
扶养；支持：
例句：
maintain a family.
供养家庭

To keep in existence; sustain:
使存在；支撑：
例句：
enough food to maintain life.
足够维持生命的食物

To defend or hold against criticism or attack:
保卫或抵制批评或进攻：
例句：
maintained his stand on taxes.
维护他在税收上的立场

To declare to be true; affirm:
断言；主张：
例句：
maintained her innocence.
坚持她的清白无辜

来源：
Middle English maintainen
中古英语 maintainen
from Old French maintenir
源自 古法语 maintenir
from Medieval Latin manutenôre
源自 中世纪拉丁语 manutenôre
from Latin manô tenôre [to hold in the hand]
源自 拉丁语 manô tenôre [拿在手中]
manô [ablative of] manus [hand] * see man- 2
manô [] manus的夺格 [手] *参见 man- 2
tenôre [to hold] * see ten-
tenôre [坚持] *参见 ten-

【引伸】
maintain.abil.ity
n.（名词）
maintain.able
adj.（形容词）
maintain.er
n.（名词）