C1. The United Nations Security Council is comprised _____of________ five permanent members: Russia, the United Kingdom, the United States, France, and China.
C2. It is compulsory _____for________ all motorcyclists to wear helmets.
C3. I’ve been corresponding _____with________ several experts in the field.
C4. He knew he could depend _____on________ her to deal with the situation.
C5. A sentence can be divided up _____into________ meaningful segments.
C6. We divided the work _____for________ us.
C7. He impressed her ______by_______ his sincerity.
C8. It is impossible to separate belief _____________ emotion.
C9. A penfriend or a pen pal is a person that you make friends ______from_______ by writing letters.
C10. It is important to keep ___in__________ touch ____with_________ the latest research.
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