YES ---- CR(R) ---- R : left-linear, C : CR and CP-closing, and Cdup/R : SN R: g(a()) -> f(g(a())) g(b()) -> c(a()) a() -> b() f(x) -> h(x) h(x) -> c(b()) CP(R): g(b()) -> f(g(a())) critical-pair-closing system C: g(b()) -> c(a()) a() -> b() f(x) -> h(x) h(x) -> c(b()) CR(C): see below. ---- CR(R) ---- R : left-linear, C : CR and CP-closing, and Cdup/R : SN R: g(b()) -> c(a()) a() -> b() f(x) -> h(x) h(x) -> c(b()) CP(R): critical-pair-closing system C: CR(C): see below. ---- CR(R) ---- R is empty.