  Resonances and continuum states of He isotopes are investigated using the
cluster orbital shell model (COSM) with the complex scaling method (CSM). We
discuss the following subjects: 1) Spectroscopic factors of the unbound nucleus
7He into the 6He-n components and their relation to the one-neutron removal
strengths of 7He. The importance of the 6He(2+) resonance is shown. 2)
Structure of five-body 0+ resonance of 8He from the viewpoint of the
two-neutron pair coupling. The monopole strengths into five-body unbound states
are also investigated. It is found that the sequential breakup process of 8He
\to 7He+n \to 6He+n+n is dominant in the monopole excitation, while the
contribution of 8He(0+_2) is negligible.
