Our English teacher often_______ us ______ her home to have a party.
A:invites, to
B:invited, to
C:invents, to
D:invented, to
将正比例函数y=3x的图象向下平移4个单位长度后,所得函数图象的解析式为( )
注:可能用到的密码子:天冬氨酸(GAC),甘氨酸(GGU、GGG),甲硫氨酸(AUG),终止密码(UAG).
下面四个图形中,∠1与∠2是对顶角的图形的个数是( )