If voltage mapped to the midterm, And current to student questions and needs, The system would be like an AC capacitor, As relative to the voltage, the current leads.

seen from Singapore
seen from Macao SAR China

seen from Malaysia

seen from United States
seen from Sweden
seen from United States
seen from China

seen from China

seen from Singapore

seen from Spain

seen from United States

seen from Italy
seen from Pakistan
seen from Ireland

seen from Italy
seen from United States
seen from China
seen from China

seen from Italy

seen from Malaysia
If voltage mapped to the midterm, And current to student questions and needs, The system would be like an AC capacitor, As relative to the voltage, the current leads.
Voltage is a sinusoid, Current leads, lags, is in phase. It takes careful concentration, To work your brain around this maze.