阅读理解。
This is the twin's(双胞胎的) room. It's a nice room. The two beds are in the room. One is Lucy's and the other
(另一个) is Lily's. They look the same. Their coats are on the beds. We can't see their shoes. They are under the
beds.
The twins have desks and chairs. Their clocks, books and pencil-boxes are on the desks. Their bags are behind
(在…后面)the chairs.
1. --- What kind(种类) of room is it?
--- It's a ________.
A. classroom
B. big room
C. bedroom
2. Which one is right?
A. Lily's coat is on the desk.
B. Lucy's shoes are under the chair
C. Two beds are in the room.
3.---Where are their bags?
--- They are _____________.
A. on the wall
B. behind the chair
C. under their beds
4. Their shoes are ____________.
A. under the desks
B. on the beds
C. under the
5. We can see _______________.
A. their shoes under the chairs
B. their clocks and books on the desks.
C. their bags are under the beds
的大小等于最大静摩擦力，且A、B的质量相等，则下列图中可以定性地描述长木板B运动的v-t图象的是
