Difference between Maintain and Keep

MAINTAIN vs KEEP: NOUN

To affirm; to support or defend by argument.
To bear the expense of; to support; to keep up; to supply with what is needed.
To continue; not to suffer to cease or fail.
To keep possession of; to hold and defend; not to surrender or relinquish.
To hold or keep in any particular state or condition; to support; to sustain; to uphold; to keep up; not to suffer to fail or decline
To adhere or conform to; keep.
To declare to be true; affirm.
To defend or hold against criticism or attack.
To keep in existence; sustain.
To provide for; support.
To keep in a condition of good repair or efficiency.
To keep in an existing state; preserve or retain.
To keep up or carry on; continue.

E.g., "keep clean"
2. To hold as true; hold.
To behave; conduct one's self.
Synonyms and Defend, Vindicate, etc. See assert.
To represent; denote.
To uphold by argument or assertion; hold to: as, to maintain the doctrine of the Trinity.
To give support or encouragement to; uphold; countenance; vindicate, as by defense or adjudication.
To hold fast; keep in possession; preserve from capture or loss: as, to maintain one's ground in battle or in argument; to maintain an advantage.
To furnish means for the subsistence or existence of; sustain or assist with the means of livelihood; provide for; support: as, to maintain a family or an army; to maintain a costly equipage.
To hold in an existing state or condition; keep in existence or continuance; preserve from lapse, decline, failure, or cessation; keep up: as, to maintain an upright attitude; to maintain a conversation.

Ensure, Establish, Retain, Asseverate, Keep up, Wield, Observe, Hold, Defend, Exert, Assert, Uphold, Keep, Preserve, Sustain

Hold on, Celebrate, Support, Living, Proceed, Observe, Save, Restrain, Sustain, Hold, Preserve, Retain, Continue, Prevent, Maintain

Cultivate, Achieve, Continue, Assure, Secure, Build, Ensure, Establish, Retain, Observe, Hold, Assert, Uphold, Keep, Preserve

Keep on, Dungeon, Sustenance, Hold on, Celebrate, Support, Living, Observe, Save, Restrain, Hold, Preserve, Retain, Prevent, Continue

Former employers maintain records of past group policies.
Maintain Mission Valley as a regional retail center.
It is very important to maintain your scissors.
There is an urgency to maintain the momentum.
Maintain Infection Control Standards in Office Practice Settings.
All the recruited candidates shall maintain bonafidehead quarters.
The higher the blood level that you need to maintain, the more vitamin D you will need to maintain that level.
MPSI to maintain positive net worth, with one state requiring that MPSI maintain positive tangible net worth.
The treasurer shall maintain custody of funds, prepare annual budget and financial statement, and maintain oversight of BRIGHT budget.
We maintain commercially reasonable safeguards to maintain the security and privacy of personal information that you provide to us.

It is also a good idea that the seller keep a copy of the Bill of Sale, and the buyer keep the original.
The clips want to jump back in so try to keep a little pressure on the shell to keep them disengaged.
Just keep checking in between other jobs, so you can keep the process going between the washer and the dryer.
Keep your lawn short and keep your puppy out of bushes and woody areas.
So keep an eye on it or keep your hand on it at all times.
To keep your glow stick going for longer, the trick is to keep putting them in the freezer.
We keep our thoughts captive, and guarded, and keep our minds busy meditating on the Word.
Select the Keep option to keep the production note in the braille.
Just keep in mind that you have to practice and keep doing these.
Keep up the fantastic work and keep me entertained.