In what properties do the first elements of a group differ from the subsequent elements of the same group?

(N/A) The first elements of a group (e.g.,$Li, Be, B, C, N, O, F$) exhibit anomalous properties compared to the rest of the elements in their respective groups due to their small size,high electronegativity,and absence of $d$-orbitals.

$1$. First element of the group	$2$. Subsequent elements of the group
They can form a maximum of $4$ bonds (e.g.,$[BF_4]^-$).	They can form more than $4$ covalent bonds (e.g.,$[Al(H_2O)_6]^{3+}$).
They form multiple bonds with themselves and other elements (e.g.,$C=C, N=N, C\equiv C, N\equiv N, C=O, C\equiv N, N=O$).	They do not typically form multiple bonds.