学生学习中的注意状态是指学生在学习活动中心理活动对学习对象的（）状态。A.指向和集中

The pile of books fell down from the shelf and ______ all over the floor.

A．scattered

B．slipped

C．extended

D．separated

A．those

B．which

C．what

D．that

______ from the apple tree.

A. It down fell

B. It fell down

C. Down fell it

D. Fell it down

________ from the apple tree

[A] It down fell

[B] there it is needed

[C] Down fell it

[D] Fell it down

How to deal with the prisoner in Biden's opinion？

A．Kill all the prisoners before shut down Guantanamo.

B．Move all the prisoners to other places before shut down Guantanamo.

C．Keep those who deserve and let the others go.

D．Amnesty all the prisoners.

I was surprised to find that they all fell in with my suggestion at once.

A．turned down

B．agreed to

C．cut off

D．carried out

______ from the apple tree.

A．It down fell

B．It fell down

C．Down fell it

D．Fell it down

A．knocked down

B．startled

C．challenged

D．fell apart

Once the novelty of watching TV and videos all day has ______, there is nothing to do.

A．worn away

B．worn down

C．worn off

D．worn out

The function of the piston rings is to ________.

A help cool the piston by transferring heat from the piston to the cylinder wall

B provide a sliding seal between the piston and cylinder wall

C scrape oil off the cylinder wall as the piston moves down on the power and intake strokes.

D all of the above