diff --git a/Tutorial/01_test_and_Pauli_matrix.py b/Tutorial/01_test_and_Pauli_matrix.py
index 8e1edb0..0318295 100644
--- a/Tutorial/01_test_and_Pauli_matrix.py
+++ b/Tutorial/01_test_and_Pauli_matrix.py
@@ -1,9 +1,6 @@
 import guan
 
-# test
 guan.test()
-
-# Pauli matrix
 sigma_0 = guan.sigma_0()
 sigma_x = guan.sigma_x()
 sigma_y = guan.sigma_y()
diff --git a/Tutorial/02_Fourier_transform_and_calculate_band_structures.py b/Tutorial/02_Fourier_transform_and_calculate_band_structures.py
index 64e46da..9d8b677 100644
--- a/Tutorial/02_Fourier_transform_and_calculate_band_structures.py
+++ b/Tutorial/02_Fourier_transform_and_calculate_band_structures.py
@@ -1,7 +1,6 @@
 import guan
 import numpy as np
 
-# Fourier transform / calculate band structures / plot figures
 k_array = np.linspace(-np.pi, np.pi, 100)
 hamiltonian_function = guan.one_dimensional_fourier_transform_with_k(unit_cell=0, hopping=1) # one dimensional chain
 eigenvalue_array = guan.calculate_eigenvalue_with_one_parameter(k_array, hamiltonian_function)
diff --git a/Tutorial/03_Hamiltonian_of_finite_size_systems.py b/Tutorial/03_Hamiltonian_of_finite_size_systems.py
index a3a8afb..1b53910 100644
--- a/Tutorial/03_Hamiltonian_of_finite_size_systems.py
+++ b/Tutorial/03_Hamiltonian_of_finite_size_systems.py
@@ -1,6 +1,5 @@
 import guan
 
-# Hamiltonian of finite size
 print('\n', guan.hamiltonian_of_finite_size_system_along_one_direction(3), '\n')
 print(guan.hamiltonian_of_finite_size_system_along_two_directions_for_square_lattice(2, 2), '\n')
 print(guan.hamiltonian_of_finite_size_system_along_three_directions_for_cubic_lattice(2, 2, 2), '\n')
\ No newline at end of file
diff --git a/Tutorial/04_some_models_in_the_reciprocal_space.py b/Tutorial/04_some_models_in_the_reciprocal_space.py
index 554d5b5..c30ef36 100644
--- a/Tutorial/04_some_models_in_the_reciprocal_space.py
+++ b/Tutorial/04_some_models_in_the_reciprocal_space.py
@@ -1,7 +1,6 @@
 import guan
 import numpy as np
 
-# Hamiltonian of models in the reciprocal space / calculate band structures / plot figures
 k_array = np.linspace(-np.pi, np.pi, 100)
 eigenvalue_array = guan.calculate_eigenvalue_with_one_parameter(k_array, guan.hamiltonian_of_square_lattice_in_quasi_one_dimension)
 guan.plot(k_array, eigenvalue_array, xlabel='k', ylabel='E', type='-k')
diff --git a/Tutorial/05_calculate_density_of_states.py b/Tutorial/05_calculate_density_of_states.py
index 63fef57..4b0a820 100644
--- a/Tutorial/05_calculate_density_of_states.py
+++ b/Tutorial/05_calculate_density_of_states.py
@@ -1,11 +1,10 @@
 import guan
 import numpy as np
 
-# calculate density of states
 hamiltonian = guan.hamiltonian_of_finite_size_system_along_two_directions_for_square_lattice(2,2)
 fermi_energy_array = np.linspace(-4, 4, 400)
 total_dos_array = guan.total_density_of_states_with_fermi_energy_array(fermi_energy_array, hamiltonian, broadening=0.1)
-guan.plot(fermi_energy_array, total_dos_array, xlabel='E', ylabel='Total DOS', type='-o')
+guan.plot(fermi_energy_array, total_dos_array, xlabel='E', ylabel='Total DOS', type='-')
 
 fermi_energy = 0
 N1 = 3
diff --git a/Tutorial/06_calculate_conductance_and_scattering_matrix.py b/Tutorial/06_calculate_conductance_and_scattering_matrix.py
index 0ee5a77..5f50d13 100644
--- a/Tutorial/06_calculate_conductance_and_scattering_matrix.py
+++ b/Tutorial/06_calculate_conductance_and_scattering_matrix.py
@@ -1,13 +1,11 @@
 import guan
 import numpy as np
 
-# calculate conductance
 fermi_energy_array = np.linspace(-4, 4, 400)
 h00 = guan.hamiltonian_of_finite_size_system_along_one_direction(4)
 h01 = np.identity(4)
 conductance_array = guan.calculate_conductance_with_fermi_energy_array(fermi_energy_array, h00, h01)
 guan.plot(fermi_energy_array, conductance_array, xlabel='E', ylabel='Conductance', type='-')
 
-# calculate scattering matrix
 fermi_energy = 0
 guan.print_or_write_scattering_matrix(fermi_energy, h00, h01)
\ No newline at end of file
diff --git a/Tutorial/07_calculate_Chern_number_and_Wilson_loop.py b/Tutorial/07_calculate_Chern_number_and_Wilson_loop.py
index d785e0e..46822df 100644
--- a/Tutorial/07_calculate_Chern_number_and_Wilson_loop.py
+++ b/Tutorial/07_calculate_Chern_number_and_Wilson_loop.py
@@ -2,12 +2,10 @@ import guan
 import numpy as np
 from math import *
 
-# calculate Chern number
 chern_number = guan.calculate_chern_number_for_square_lattice(guan.hamiltonian_of_one_QAH_model, precision=100)
-print('\nChern number=', chern_number)
+print('\nChern number=', chern_number, '\n')
 
-# calculate Wilson loop
 wilson_loop_array = guan.calculate_wilson_loop(guan.hamiltonian_of_ssh_model)
 print('Wilson loop =', wilson_loop_array)
 p = np.log(wilson_loop_array)/2/pi/1j
-print('p =', p, '\n')
\ No newline at end of file
+print('\np =', p, '\n')
\ No newline at end of file
diff --git a/Tutorial/08_read_and_write.py b/Tutorial/08_read_and_write.py
index 101655f..6cad642 100644
--- a/Tutorial/08_read_and_write.py
+++ b/Tutorial/08_read_and_write.py
@@ -1,7 +1,6 @@
 import guan
 import numpy as np
 
-# read and write
 x_array = np.array([1, 2, 3])
 y_array = np.array([5, 6, 7])
 guan.write_one_dimensional_data(x_array, y_array, filename='one_dimensional_data')