Fill in prepositions if necessary: 1) he must go to st.petersburg . 2) we take our written . 3) our studies . 4) what do you ? 5) all the students of our group will take part in the . 6) may i ring you morning? 7) my elder brother is a doctor. he often .8) is there dean's office? 9) i must go and see o'. 10) new laboratory. 11) blackboard. do you see any it? 12) who today? 13) will you blackboard? 14) you may place. dining-table there is a cupboard.