填空题 If it had not been for Professor Russel standing up for him, he 1 (have to leave).
【正确答案】
【答案解析】would have had to leave[解析] if it had not been for...“要不是因为……”(表示过去事情)；if it were not for...“要不是因为……”(表示现在的事情)。stand up for(=support)“支持”。