A small trick that you can do is to create a matrix of either of those 2 vectors and then paste the matrices like below.
Just a small trick,
Suppose the matrices where letters = c ("a","b","c","d") and numbers = c (1,2,3,4,5).
Now create a matrix of any 1 vector and then paste matrix with the vector this will fetch you combined vector as you wanted.
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Pasting 2 vectors directly will give result as below
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