Show that $S_n$ can be generated from the two-cycles $(1\,2),(1\,3),\dotsc,(1\,n)$.

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Show that $S_n$ can be generated from the two-cycles $(1\,2),(1\,3),\dotsc,(1\,n)$.

I have a lemma given:

Lemma: Every $\sigma \in S_n$ can be written as a product of transpositions.

So I concluded that all I need to show is that $(1\,2),(1\,3),\dotsc,(1\,n)$ can generate all transpositions. Now, we have

$$(i\, j) = (1\,i)*(1\,j)*(1\,i)$$

for any $i, j \in \{2,\dotsc,n\}$ implying that we can generate all transpositions from the given two-cycles. Then I apply the lemma to conclude that every $\sigma \in S_n$ can be generated from the two-cycles. Please give me some feedback on my proof please!