  Recently the concept of compositeness has been developed so as to distinguish
whether interested hadrons are hadronic molecules or not. Here, in terms of
compositeness, we investigate $\bar{K} N$ molecular structure of the $\Lambda
(1405)$ resonance with the $\Lambda (1405)$ radiative decay and $K \bar{K}$
molecular structure of the $a_{0} (980)$ and $f_{0} (980)$ resonances with the
$a_{0} (980)$-$f_{0} (980)$ mixing.
