例句與造句

1. Finally, in papers on the " Mathematical Formulation of the Quantum Theory of Electromagnetic Interaction " in 1950 and " An Operator Calculus Having Applications in Quantum Electrodynamics " in 1951, he developed the mathematical basis of his ideas, derived familiar formulae and advanced new ones.
2. It's difficult to find operator calculus in a sentence. 用operator calculus造句挺難的