---How long do you think it is ______he took up the job?--- Half a year at least.
They did not sell a single car for a month and had to ________ some workers.
I don’t think I will need any money but I will bring some _______.
The disease failed to _______ to the new drugs the doctor used.
The experiment, though they had tried their best, ________ to be a failure.
Mr. White promised that he would tell me the result _______ he knew it.