荣获二等功的退役士兵，由部队按照20%增发一次性退役金。
参考答案：错
Disthinguished guests and friends, welcome to our school! ________the ceremony of the 50th anniversary this morning are our alumni (校友) from home and abroad.
A．Attend
B．To attend
C．Attending
D．Having attended
先化简，后求值：4xy-（2x2+5xy-y2）+2（x2+3xy），其中x=3，y=-2．
