更正：
1.Our English teacher is a middle-aged man who (is)...
从句时态一般会和主句时态对应.
不过此句缺少后文,所以如果真有错,只能把was改成is；
2.it's said that he (去掉was) graduated from a famous university in 1973.He is strict with us in our studies.
graduate为不及物动词,没有被动语态.