封发关系分为（）三种。
A、互封、直封、临封
B、集封、直封、临封
C、单封、混封、集封
D、单封、混封、临封
参考答案：A
租赁合同成立的有效要件？
Describe with examples the lexical loss which occurred in Old English and Middle English. Do you think the loss of words inevitable What do you think of the process of lexical loss
