乘人器每个座椅只准乘坐()人。
A.1
B.2
C.3
参考答案:A
There is no doubt ______ you'll be warmly welcomed by people there.
A.if
B.whether
C.that
D.about
下列离子中,电子数和质子数与Na+相同的是 [ ]
A、
B、
C、
D、