一Be careful , you will make mistakes in your exams. —I know that,Mum. One can never be too careful.
The boss makes the workers ________ long hours every day.
-- Jim fell off the bike and broke his right leg. --_____.
We thought it was a story and we all got .
---What will you do if it _____ rain tomorrow? --- I’m not sure.
They found difficult to finish the work in such a short time.