strength
There is some doubt ____ the sick schoolboy can join in the English evening party on Sunday.
---- How long ____ at this job? ---- Since 1990.
___ I know he will stay here for half a year.
_____ the government agrees to give extra money , the theatre will have to close.
----Iam sorry to have ____ too much of your time. ----That's OK, and I am glad to help you.