the present invention will be described more fully hereinafter with reference to the accompanying drawings , in which exemplary embodiments of the invention are shown . as those skilled in the art will realize , the described embodiments may be modified in various different ways , all without departing from the spirit or scope of the present invention . as shown in fig1 , an engine 105 includes a first cylinder ( cyl . # 1 ) a second cylinder ( cyl . # 2 ), a third cylinder ( cyl . # 3 ), and a fourth cylinder ( cyl . # 4 ). also , an exhaust camshaft 115 and an intake camshaft 120 arc disposed to the cylinders . a first cylinder deactivation portion 217 a for exhaust and a second cylinder deactivation portion 217 b for intake are provided in the first cylinder ( cyl . # 1 ). a third cylinder deactivation portion 217 c for exhaust and a fourth cylinder deactivation portion 217 d for intake are provided the second cylinder ( cyl . # 2 ). a fifth cylinder deactivation portion 217 e and a sixth cylinder deactivation portion 217 f are provided in the third cylinder ( cyl . # 3 ). a seventh cylinder deactivation portion 217 g and an eighth cylinder deactivation portion 217 h are provided in the fourth cylinder ( cyl . # 4 ). a first hydraulic pressure line is provided to cylinder deactivation portions 217 a to 217 h . a check valve 100 is provided in the first hydraulic pressure line . control valves ( e . g ., solenoid valves ) are disposed on branch lines that are extended to the cylinder deactivation portions 217 a to 217 h . a variable valve timing portion 112 is disposed at one end of each camshaft 115 , 120 , and a second hydraulic pressure line is provided to the variable valve timing portions 112 . a control valve 110 is disposed in branch lines to each of the camshafts 115 and 120 . the deactivation portions 217 a to 217 h arc operated alternately . this prevents spark plugs disposed in any one particular cylinder from becoming fouled by oil . also , bore transformation of a particular cylinder is prevented . referring to fig2 , a first variable valve lifter 405 a is provided in an exhaust port of the first cylinder ( cyl . # 1 ) and a second variable valve lifter 405 b is provided in an intake port of the first cylinder ( cyl . # 1 ). a third variable valve lifter 405 c and a fourth variable valve lifter 405 d are provided in the second cylinder ( cyl . # 2 ). a fifth variable valve lifter 405 e and a sixth variable valve lifter 405 f are provided in the third cylinder ( cyl . # 3 ). a seventh variable valve lifter 405 g and an eighth variable valve lifter 405 h are provided in the fourth cylinder ( cyl . # 4 ). the variable valve lifters 405 a to 405 h control a swing arm ( not shown ) so as to control a lift amount of the valve in fig2 . the valve controlled by the swing arm is adjusted in three steps of high , low , or medium . a first control shaft 410 a and a second control shaft 410 b are provided so as to control the variable valve lifters 405 a to 405 h . the first control shaft 410 a is provided at the exhaust side adjacent to the exhaust camshaft 115 , and the second control shaft 410 b is provided at the intake side adjacent to the intake camshaft 120 . lifting distances of the exhaust valve and the intake valve are adjusted sequentially according to rotating positions of the first and second control shafts 410 a and 410 b . a third hydraulic pressure line is provided to the first and second control shafts 410 a and 410 b . a check valve 402 is provided in the third hydraulic pressure line . the first control shaft 410 a simultaneously controls valves of the exhaust side and the second control shaft 410 b simultaneously controls valves of the intake side . a first rotation angle control motor 400 a is provided at one end of the first control shaft 410 a , and a second rotation angle control motor 400 b is provided at one end of the second control shaft 410 b . referring to fig3 , a ninth variable valve lifter 505 a is provided in an exhaust port of the first cylinder ( cyl . # 1 ), and a tenth variable valve lifter 505 b is provided in an intake port of the first cylinder ( cyl . # 1 ). a eleventh variable valve lifter 505 c and a twelfth variable valve lifter 505 d are provided in the second cylinder ( cyl . # 2 ). a thirteenth variable valve lifter 505 c and a fourteenth variable valve lifter 505 f are provided in the third cylinder ( cyl . # 3 ). a fifteenth variable valve lifter 505 g and a sixteenth variable valve lifter 505 h are provided in the fourth cylinder ( cyl . # 4 ). the ninth to sixteen variable valve lifters 505 a to 505 h control a rocker arm ( not shown ) so as to control a lift amount of a valve in fig3 . the valve controlled by the rocker arm is adjusted in three steps of high , low , or medium . a third control shaft 510 a and a fourth control shaft 510 b are provided so as to control the variable valve lifters 505 a to 505 h . the third control shaft 510 a is provided at an exhaust side and adjacent to the exhaust camshaft 115 , and the fourth control shaft 510 b is provided at an intake side and adjacent to the intake camshaft 120 . lifting distances of the exhaust valve and the intake valve are adjusted continuously according to rotating positions of the third and fourth control shafts 510 a and 510 b . a fourth hydraulic pressure line is provided to the third and fourth control shafts 510 a and 510 b . a check valve 502 is provided in the fourth hydraulic pressure line . the third control shaft 510 a simultaneously controls valves of the exhaust side and the fourth control shaft 510 b simultaneously controls valves of the intake side . a third rotation angle control motor 500 a is provided at one end of the third control shalt 510 a , and a fourth rotation angle control motor 500 b is provided at one end of the fourth control shaft 510 a . as shown in fig4 , an 14 engine has four cylinders ( cyl . # 1 , 2 , 3 , 4 ), where the second and third cylinders ( cyl . # 2 , 3 ) are classified into a first group , and the first and fourth cylinders ( cyl . # 1 , 4 ) are classified into a second group . the first group and the second group are alternately deactivated in the 14 engine . the variable valve lift system can be operated in different cylinders when cylinders are alternately deactivated . the variable valve lift system includes systems that are operated by a rocker arm or a swing arm . the first , third , and fifth cylinders ( cyl , # 1 , 3 , 5 ) and the second , fourth , and sixth cylinders ( cyl , # 2 , 4 , 6 ) are alternately deactivated in a v6 engine . the first , fourth , sixth , and seventh cylinders ( cyl , # 1 , 4 , 6 , 7 ) and the second , third , fifth , and eighth cylinders ( cyl , # 2 , 3 , 5 , 8 ) are alternately deactivated in a v8 engine . referring to fig5 , all cylinder deactivation portions ( cda ) in group 1 and group 2 are operated in a fuel cut state . when the cylinder deactivation portions ( cda ) in group 1 are operated in a range from 2000 to 3500 rpm , the variable valve lifter ( vvl ) can be operated in three steps of high , low , or medium in group 2 . also , when cylinder deactivation portions ( cda ) of group 2 are operated in a range from 2000 to 3500 rpm , the variable valve lifter ( vvl ) can be operated in three steps of high , low , or medium in group 1 . the variable valve lifters ( vvl ) of groups 1 and 2 are operated and the cylinder deactivation portions ( cda ) of groups 1 and 2 are not operated from idle to 2000 rpm . at full load , the variable valve lifter ( vvl ) is operated in medium at a low speed and the variable valve lifter ( vvl ) is operated in high at a high speed . the cylinder deactivation portion ( cda ) does not operate at a full load . while this invention has been described in connection with what is presently considered to be practical exemplary embodiments , it is to be understood that the invention is not limited to the disclosed embodiments , but , on the contrary , is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims .