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16. I’ve been working for “Mr. Z and Co.” ____ last summer.
a) from b) for
c) until d) since
17. I _____ on this project for two months.
a) am working b) worked
c) have been working d) was working

16. I’ve been working for “Mr. Z and Co.” ____ last summer.  d) since 17. I _____ on this project for two months. c) have been working