____seems very hard to reach the top of the mountains.
#55842
A
That
B
This
C
I
D
It
推荐题目
Is this your father? No, ________. 
#55854
A
it is
B
it isn’t
C
he is
D
he isn’t
-- ________Alan’s pens? --Yes, they’re ________.
#55802
A
Is this; his
B
Are these; his
C
Is this; her
D
Are these; her