正弦波

sine wave / simple harmonic vibration

first month of the lunar year

straight / upright / proper / main / principal / to correct / to rectify / exactly / just (at that time) / right (in that place) / (math.) positive

(math.) sine

bow string / string of musical instrument / watchspring / chord (segment of curve) / hypotenuse / CL:根[gen1]

Poland / Polish / abbr. for 波蘭|波兰[Bo1 lan2]

wave / ripple / storm / surge