Phrases using 'on' On duty: doing the work that you should be doing On guard: guarding something important On your toes: very alert watching out for something to happen On approval: (of goods) supplied on condition that they may be returned if not satisfactory On demand: to get something when you ask for it Can you fit each one of the phrases above into these sentences? 1. The soldiers are ...... outside the palace. 2. You can get a visa ....... if you go to the consulate. 3. I am ....... all weekend in case of accidents. 4. I have bought this camera ...... 5. You have to be ........ with the new English teacher. Answers: on guard/on demand/on duty/on approval/on your toes
