Observation is the best teacher.
Of all eloquence a nickname is the most concise, of all arguments the most unanswerable.
Of all the possessions of this life, fame is the noblest; when the body has sunk into the dust,the great name still lives.
Oh,how nice.Sorry,I've got to go now.
Oh,I'm sorry to hear that.
Oh,really?I'm moving there too.
Oh,thank you.How have you been these days?
Oh,that's not good.
Old age is like everything else. To make a success of it, you've got to start young.
Old friends and old wine are best.
On earth there is nothing great but man;in the man there is nothing great but mind.
On life's earnest battle they only prevail, who daily march onward and never say fail.
On Monday morning don't be looking for Saturday night.
On Sundays I often spend some time reading in the library.
On the desk.
Once a beggar, always a beggar.
Once bitten,twice shy.
Once virtue is lost, all is lost.
One cannot help being old, but one can resist being aged.
One cannot put back the clock.
One cannot serve God and Mammon.
One careless move may lose the whole game.
One cloud is enough to eclipse all the sun.
One enemy is too many, and a hundred friends too few.
One eyewitness is better than two hearers.
One father is more than a hundred schoolmasters.
One fifth of the people are against everything all the time.
One flower does not make a spring.
One gives nothing so liberally as advice.
One good turn deserves another.
One half of knowing what you want is knowing what you must give up before you get it.
One in love fears no storm; he fears only the death of love.
One is never too old to learn.
One link broken,the whole chain is broken.
One loses by pride and gains by modesty.
One loses time seeking for words; one kiss brings understanding.
One love drives out another.
One machine can do the work of 50 ordinary men, but no machine can do the work of one extraordinary man.
One man,no man.
One man's fault is another man's lesson.
One may overcome a thousand men in battle.but he who conquers himself is the greatest victor.
One must draw back in order to leap better.
One must draw the line somewhere.
One never goes to the temple for no reason.
One of the difficult tasks in this world is to convince a woman that even a bargain costs money.
One of the greatest pleasures in life is conversation.
One of these days in none of these days.
One pound of learning requires ten pounds of common sense to apply it.
One should always live in the best company, whether it be of books or of men.
One should eat to live,not live to eat.
One strand of silk doesn't make a thread; one tree doesn't make a forest.
One swallow does not make a summer.
One thing I know, that is, know nothing.
One thing I know:The only ones among you who will be really happy are those who will have sought and found how to serve.
One today is worth two tomorrow.
One touch of nature makes the whole world kin.
One tree does not make a forest.
One volunteer is better than ten forced men.
One who keeps abreast of the time remains young.
One wonderful thing about a vacation is that it makes you feel good enough to go back to work and poor enough so that you have to.
One's ability falls short of one's wishes./ The spirit is willing, but the flesh is weak.
One's sin will find one out.
Only a life lived for others is a life worthwhile.
Only by working hard can we reap a bumper harvest.
Only the person who has faith in himself is able to be faithful to others.
Only the selfless can be fearless.
Only three days.
Only when one plunges into the powerful current of the times will one's life shine brilliantly.
Open confession is good for the soul.
Open different locks with different keys.
Open your books and turn to page 20.
Opinions should be formed with great caution-and changed with greater.
Opportunities do not wait.
Opportunity is rare, and a wise man will never let it go by him.
Optimist:A man who gets treed by a lion but enjoys the scenery.
Ordinary people think merely how they will spend time,a man of intellect tries to use it.
Other people's defects are good teachers.
Other times,other manners.
Our best thought comes form others.
Our bravest and best lessons are not learned through success,but through misadventure.
Our faults irritate us most when we see them in others.
Our greatest glory consists not in never falling but in rising every time we fall.
Our mightiest feeling are always those which remain most unspoken.
Our team beat their team yesterday.
Overeating will cause indigestion.