trouble(battery_broken):-order2(battery_broken),!.
trouble(the_crystal_oscillator_broken):-order(frequent_creep),!.
trouble(cut_down_lose_reality):-order3(work_point_not_suitable),order(cut_top_lose_reality),!.
trouble(over_load_lose_reality):-order3(work_point_not_suitable),order(cut_tail_lose_reality),!.
trouble(the_low_frequent_transistor_burned):-order3(the_low_frequent_transistor_broken),not order3(work_point_not_suitable),!.
trouble(the_high_frequent_transistor_burned):-order3(the_high_frequent_transistor_broken),not order3(work_point_not_suitable),!.
trouble(l_burned):-order3(go_back_broken),order(c_well),!.
trouble(r_of_transistor_not_suitable):-order1(low_frequent_area_broken),order(the_sound_slightly),!.
trouble(battery_C_opened):-order3(the_overall_arrangement_of_the_component_is_unreasonable),order(with_alternating_current_sound),!. 
trouble(microphone_parameter_improper_to_supply_power_resistance):-order(the_microphone_is_too_sensitive),!.
trouble(microphone_parameter_improper_to_supply_power_resistance):-order(the_microphone_is_too_obtuse),!. 
trouble(voltage_of_battery_is_too_low):-order(the_receivable_distant_is_too_short),order(the_light_is_dark),!.
trouble(nearly_aerial_pass_short_or_nearby_have_tall_and_big_building):-order(the_receivable_distant_is_too_short),not order(the_light_is_dark),!.




order3(work_point_not_suitable):-order(lose_reality),!.
order3(the_overall_arrangement_of_the_component_is_unreasonable):-order(whistle),!.
order3(the_high_frequent_transistor_broken):-not order2(battery_broken),order(the_high_frequent_transisor_cold),!.
order3(go_back_broken):-not order2(battery_broken),order(the_high_frequent_transisor_hot),!.
order3(the_low_frequent_transistor_broken):-not order2(battery_broken),order(microphone_well),!.



order2(not_r_broken):-order1(low_frequent_area_broken),order(there_is_no_sound),!.
order2(battery_broken):-order1(high_frequent_area_broken),not order(the_light_shine),!.

order1(low_frequent_area_broken):-order(the_receiver_with_silent_noise),!.
order1(high_frequent_area_broken):-not order(the_receiver_with_silent_noise),!.







straight_antenna(X):-ask(straight_antenna,X).
order(X):-ask(order,X).




ask(A,V):-known(y,A,V),!.
ask(A,V):-known(_,A,V),!,fail.
ask(A,V):-write(A:V),write('?'),read(Y),asserta(known(Y,A,V)),Y==y.