Подчеркните в каждом предложении глагол-сказуемое и определите его видо-временную форму и залог. a) 1. astronomers have measured the exact length of the day. 2. astronomers find that the day is increasing by 0.002 seconds each century. b) 1. the chemical properties of an element are determined by the orbiting electrons. 2. as a rule one great discovery is generally followed by numerous others
а) 1) have measured (Present Perfect, active voice)
2) find (Present Simple, active voice)
b) 1) are determined (Present Simple, passive voice)
2) is followed (Present Simple, passive voice)