YES
We show the termination of the TRS R:

  f(a(),h(x)) -> f(g(x),h(x))
  h(g(x)) -> h(a())
  g(h(x)) -> g(x)
  h(h(x)) -> x


-- SCC decomposition.

Consider the dependency pair problem (P, R), where P consists of

p1: f#(a(),h(x)) -> f#(g(x),h(x))
p2: f#(a(),h(x)) -> g#(x)
p3: h#(g(x)) -> h#(a())
p4: g#(h(x)) -> g#(x)

and R consists of:

r1: f(a(),h(x)) -> f(g(x),h(x))
r2: h(g(x)) -> h(a())
r3: g(h(x)) -> g(x)
r4: h(h(x)) -> x

The estimated dependency graph contains the following SCCs:

  {p1}
  {p4}


-- Reduction pair.

Consider the dependency pair problem (P, R), where P consists of

p1: f#(a(),h(x)) -> f#(g(x),h(x))

and R consists of:

r1: f(a(),h(x)) -> f(g(x),h(x))
r2: h(g(x)) -> h(a())
r3: g(h(x)) -> g(x)
r4: h(h(x)) -> x

The set of usable rules consists of

  r2, r3, r4

Take the reduction pair:

  generalized weighted path order (>=MG, >G)
  
    base order 1:
  
      trivial reduction triple (T x T, T x T, Φ)
  
    base order 2:
  
      lexicographic combination of reduction triples:
      
        1. marked-algebra reduction triple (>=A, >=A!, >A!):
        
          max/plus interpretation on natural numbers:
          
            f#_A(x1,x2) = max{0, x1 - 9, x2 - 8}
            a_A = 0
            h_A(x1) = x1 + 1
            g_A(x1) = max{8, x1 + 2}
            f#!_A(x1,x2) = x2 + 2
            a!_A = 9
            h!_A(x1) = max{7, x1 + 6}
            g!_A(x1) = 3
        
        2. marked-algebra reduction triple (>=A, >=A!, >A!):
        
          matrix interpretation with standard point-wise order:
          
            carrier: N^1
            order: standard order
            interpretations:
              f#_A(x1,x2) = 0
              a_A() = 1
              h_A(x1) = x1 + 1
              g_A(x1) = x1 + 3
              f#!_A(x1,x2) = x2
              a!_A() = 2
              h!_A(x1) = 3
              g!_A(x1) = 1
        
  
    partial status:
  
      pi(f#) = [1]
      pi(a) = []
      pi(h) = [1]
      pi(g) = []

The following rules are removed:

  p1

Then no dependency pair remains.

-- Reduction pair.

Consider the dependency pair problem (P, R), where P consists of

p1: g#(h(x)) -> g#(x)

and R consists of:

r1: f(a(),h(x)) -> f(g(x),h(x))
r2: h(g(x)) -> h(a())
r3: g(h(x)) -> g(x)
r4: h(h(x)) -> x

The set of usable rules consists of

  (no rules)

Take the reduction pair:

  generalized weighted path order (>=MG, >G)
  
    base order 1:
  
      trivial reduction triple (T x T, T x T, Φ)
  
    base order 2:
  
      lexicographic combination of reduction triples:
      
        1. marked-algebra reduction triple (>=A, >=A!, >A!):
        
          max/plus interpretation on natural numbers:
          
            g#_A(x1) = 0
            h_A(x1) = max{0, x1 - 10}
            g#!_A(x1) = max{1, x1 - 7}
            h!_A(x1) = max{3, x1 - 6}
        
        2. marked-algebra reduction triple (>=A, >=A!, >A!):
        
          matrix interpretation with standard point-wise order:
          
            carrier: N^1
            order: standard order
            interpretations:
              g#_A(x1) = x1
              h_A(x1) = x1 + 1
              g#!_A(x1) = x1 + 5
              h!_A(x1) = 4
        
  
    partial status:
  
      pi(g#) = [1]
      pi(h) = [1]

The following rules are removed:

  p1

Then no dependency pair remains.