6 Answers

I have been working with my 3 and 5 yr. old grandkids on just this lately.  They are so smart today, we were much slower 60 yrs ago...

You put two pairs of marbles or buttons near each other, Then you say, '' If I added these together, how many will there be ? "    Then you put them together and count them. Obviously , there are 4. And that's how you add.

If you are referring to numbers, or numbers which represent a quantity of something, I mostly do that mentally, without writing it down.  

Basic mathematical addition involves combining quantities of the same thing/abstract to increase the total.  

add |ad| verb [ with obj. ] 1 join (something) to something else so as to increase the size, number, or amount: a new wing was added to the building | some box offices now add on a handling charge | (as adj. added) : one vitamin tablet daily will give added protection | [ no obj. ] : this development added to the problems facing the staff. • [ no obj. ] (add up) increase in amount, number, or degree: watch those air miles add up! • put or mix (an ingredient) together with another as one of the stages in the preparation of a dish: add the flour to the eggs, stirring continuously. • put (something) in or on something else so as to improve or alter its quality or nature: chlorine is added to the water to kill bacteria | (as adj. added) : the fruit juice contains no added sugar. • contribute (an enhancing quality) to something: the canopy will add a touch of class to your bedroom. 2 put together (two or more numbers or amounts) to calculate their total value: they added all the figures up | add the two numbers together | [ no obj. ] : children learned to add and subtract quickly and accurately. • [ no obj. ] (add up to) amount to: this adds up to a total of 400 calories | figurative : these isolated incidents don't add up to a true picture of the situation. • [ no obj., usu. with negative ] (add up) informal seem reasonable or consistent; make sense: many things in her story didn't add up. 3 [ reporting verb ] say as a further remark: [ with direct speech ] : “I hope we haven't been too much trouble,” she added politely | [ with obj. ] : we would like to add our congratulations | [ with clause ] : he added that few of America's allies would support military action. ORIGIN late Middle English: from Latin addere, from ad- ‘to’ + the base of dare ‘put.’ ADD |e?di??di?| abbreviation • analog digital digital, indicating that a music recording was made in analog format before being mastered and stored digitally. • attention deficit disorder.

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