The air intake passage is arranged to introduce {HEAD ~ air} to the chamber through a throttle valve for regulating {TAIL ~ an amount} of the air with an opening degree thereof 
The air intake passage is arranged to introduce { HEAD ~ air } to the chamber through a throttle valve for regulating { TAIL ~ an amount } of the air with an opening degree thereof
OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH