ROSE TO LOVER,SMELL IN HANDS - 送人玫瑰，手有余香

It's a good thing to help others, it makes person happy.
In China, there is a famous saying, called: "送人玫瑰，手有余香", the same expression in English is that ‘Rose to lover, Smell in hands’, that is to say, to help others, others will be happy to help you.
Therefore, “送人玫瑰，手有余香” is a very useful expression in Chinese Mandarin.
You are welcome to correct my mistakes. Thank you very much.

James:

Your first sentence is actually two seperate sentences. Notice that both sentences have a subject + verb + noun phrase/object

It is a good thing to help others. It makes a person happy. 

There is more than one way to change this into one sentence

First, ask yourself what is the focus of the first sentence. Is it doing good things? Is it helping others? Is it doing good things to help others.

Whatever you decide, you must get rid of the verb in the first sentence or make the first sentence into a clause and get rid of the subject in the second sentence and then you will have ...

Doing good things to help people makes a person happy.

Doing good things to help people makes me happy.

James:

In your third sentence, I will give you an "A" grade for trying to write a long, complex sentence.

But in order to write a long, complex sentence, you must make sure you only have 1 subject + verb phrases and all your other thoughts must be written as phrases.

In China, there is a famous saying, called: "送人玫瑰，手有余香", the same expression in English is that similiar to the English expression, 'Rose to lover, Smell in hands’, that is to say means, "to help By helping others, others will be happy to help you.

In China, there is a famous saying: "送人玫瑰，手有余香", smiliar to the English expression, ‘Rose to lover, Smell in hands’, with a similiar meaning, "By helping others, others will be happy to help you."

The same expression in English is "Rose to lover, Smell in hands" has a subject and a verb phrase so I took away the verb in order to change that sentence into a phrase. I did the same thing with your other verbs ... I either took away the verb completely or added a preposition in front of the verb to make it into a phrase.

Finally, your last sentence:

You are welcomed to correct my mistakes. Thank you very much in advance.

The reason why the word "welcome" should be written in the past tense "welcomed" is becasue when new people read your post, they must have already arrived on this web page in order to read what you wrote ... 

So welcomed is your prediction that people will have come to read what you wrote.

Now the entire notebook should read as follows:

Doing good things to help people makes a person happy. In China, there is a famous saying: "送人玫瑰，手有余香", smiliar to the English expression, ‘Rose to lover, Smell in hands’, with a similiar meaning, "By helping others, others will be happy to help you."

You are welcomed to correct my mistakes. Thank you in advance.

ROSE TO LOVER,SMELL IN HANDS - 送人玫瑰，手有余香 Give a rose to someone and there will be lingering fragrance in your hand.

It's a good thing to help others, it makes person the helper happy. Better to say, "... makes the one helping will feel good too."]

In China, there is a famous saying, called: "送人玫瑰，手有余香", the same expression in English is that ‘Rose to lover, Smell in hands’, <em>Give a rose to someone and there will be lingering fragrance in your hand.  </em>that This means is to say, that to help others, others will be happy to help and you too will be benefited. Therefore, “送人玫瑰，手有余香” [Don't use the term written in Chinese again. It is considered boring and can be quite insulting to the intelligence of the reader since you had told us this term already] This is a very useful expression in Chinese Mandarin. [This is also considered very rude because it implies truth only in Mandarin. Worse still, you will be perceived as a racist].

You are most [[You must have this word here to sound more polite.  It would be better to rephrase it as, "Please, correct my mistakes"] welcome to  correct my mistakes. Thank you very much.

An English equivalent is, "Smile and the world smiles with you".  Thank you too for I have learnt a new Chinese phrase too :) 

ROSE TO LOVER, SMELL IN HANDS - 送人玫瑰，手有余香

It's a good thing to help others; it makes a person happy.
In China, there is a famous saying: "送人玫瑰，手有余香". In English it means, ‘Rose to lover, Smell in hands.' That is to say, "By helping others, others will be happy to help you."
Therefore, “送人玫瑰，手有余香” is a very useful expression in Chinese Mandarin.
You are welcome to correct my mistakes. Thank you very much.