А) Перепишите следующие предложения; подчеркните в каждом из них глагол-сказуемое, стоящее в Perfect, и определите его временную форму (Present, Past или Future) и залог (Active или Passive).
1. Our research had been finished by the end of the year.
2. By the beginning of the year their new office will have been built.
3. We have just received your letter.
б) Перепишите следующие предложения; подчеркните в каждом из них глагол-сказуемое и определите его видовременную форму и залог.
1. I had done my work by 6 o'clock yesterday.
2. This experiment is being done right now.
3. I will write my report tomorrow.