II.Put the undertined verbs in the sentences in Past Perfect Tense: 1. Ampere determined the difference between the current and the static charges before giving the current direction
2. Men of science formed a lot of theories after Volta produced a source of continuous current.
3. By 1753 Franklin made an important contribution to the science of electricity
4. Galvani observed the experiments with the frogs' legs before Volta began to carry on similar experiments.
5. Volta spent several years before he generated a continuous current.
1. Ampere had determined the difference between the current and the static charges before giving the current direction
2. Men of science formed a lot of theories after Volta had produced a source of continuous current.
3. By 1753 Franklin had made an important contribution to the science of electricity
4. Galvani had observed the experiments with the frogs' legs before Volta began to carry on similar experiments.
5. Volta had spent several years before he generated a continuous current.