Put the verbs given in brackets in the appropriate tense. translate the sentences: while the properties of filterable viruses (исследовались) the scientist (проводил) numerous experiments. 2. when the physician (приближался) the patient’s bedside loud coughing (послышался) in the ward. 3. now the professor (читает) a lecture in which the properties of anaerobic microorganisms (анализируются).

1. While the properties of filterable viruses (were being investigated) the scientist (conducted) numerous experiments.
2. When the physician (was approaching) the patient’s bedside loud coughing (was heard) in the ward.
3. Now the professor (is reading) a lecture in which the properties of anaerobic microorganisms (are analyzed).