A．back and froB．back and forthC．to and forthD．fro and to

A．back

B．down

C．over

D．about

A.back and forth

B.down and up

C.in and out

D.back and front

The union leader decided to______the government on its action.

A．back

B．behind

C．on

D．before

You can' t ______your promise; all the people here are depending on you.

A．back off

B．back up

C．back on to

D．back out of

The purpose of the author in writing the text is to

A．back up Macdonald.

B．introduce the argument about the plan for secret terror trials.

C．criticise the bill because of the indifference to the terrorist's basic rights.

D．argue for the independence of jury trials.