说教学是德育的基本途径就是意味着教学惟一，其它的教育途径并不重要。
参考答案：错
When________there, the postman found the door locked and then stopped ______the letter under it. [ ]
A. reaching; to stick
B. reached; to stick
C. reaching; sticking
D. reached; sticking
什么叫ELISA，ELISA有哪三种基本反应类型？
