For instance, in our investigations for SMT (Section 3.1), the Formally SCFG based hierarchical phrase-based model (hereinafter FSCFG) (Chiang, 2007) has a better generalization capability than a Linguistically motivated STSSG based model (hereinafter LSTSSG) <cite>(Zhang et al., 2008)</cite> , with 5% rules of the former matched by NIST05 test set while only 3.5% rules of the latter matched by the same test set.