--The research on the new bird flu virus vaccine is challenging and demanding. Who do you think can do the job? ---____ my students have a try?
The treatment will continue until the patient reaches the point _______he can walk safely.
--- How can you keep slim as a mother of two? --- I have been _______in the gym for years.
He has spent I think a lot _______time in reading than she has.
You say he works hard; so he does,and_______.
I will never know what was on his mind at the time,and nor will_______.