It is _________ taking the trouble _________ a job fully to new employees．

worthy; explaining

worthwhile; to explain

worthy; to explain

worthwhile; explaining

Thanks for giving me _________ advice, but it’s difficult _________ me to carry it out．

such a good; for

so good; for

such good; for

so good a; for

If you _________ of Mary, ask her to come and see me．

lose sight of

catch sight of

are in the sight of

are at the sight of

It was in the university ten years ago, _________ they met in September for the first time, _________ they fell in love with each other．

that; when

when; that

that; where

where; that

Professor Smith, along with his assistant, _________ on the project day and night to meet the deadline．

work

working

is working

are working

Some researchers believe that there is no doubt _________ a cure for AIDS will be found．

which

that

what

whether

If you go by _________ train, you can have quite a comfortable journey, but make sure that you get ________ fast one．

the; the

/; a

the; a

/;/

A month ago ,I bought an ancient vase, _________ was very reasonable．

which price

the price of which

its price

the price of whose

It is universally _________ that dogs have a good sense of smell．

acknowledged

acknowledging

to be acknowledged

knowledge

Ladies and gentlemen, I have the great privilege _________ introducing our speaker for tonight．

in

of

about

on