Answer: B) For
Explanation for this question is being written.
Answer: A) Before
Answer: A) From / to.
Answer: C) On
Answer: B) In
Answer: B) At weekends.
Answer: C) Yes, 24 hours a day, everyday.
Answer: A) On
Answer: A) With, till.
Answer: A) By
Answer: C) ON
Answer: B) Ago
Answer: C) Time
Answer: C) In
Answer: A) At
Answer: B) On
Answer: A) During
Answer: A) Since
Answer: A) In
Answer: B) We usually work on every Sunday.
Answer: A) Preposition
Answer: D) For
Answer: B) At
Answer: C) At
Answer: A) True
Answer: B) By
Answer: C) For
Answer: A) For
Answer: A) On completion of a research and educational course.
Answer: C) Since
Answer: B) Since
Answer: E) On
Answer: A) AT
Answer: C) Upon their first meeting.
Answer: B) False
Answer: A) Of
Answer: A) Until
Answer: C) All