A. explain B. explaining C. to explain D. explained
A. pay B. paid C. to pay D. paying
A. is completed B. had been completed C. has completed D. had completed
A. are called B. being called C. be called D. called
A. sparing B. to spare C. spare D. spared
A. If B. While C. Until D. Although
A. before B. while C. as D. since
A. if B. unless C. when D. since
A. Even though B. As if C. In that D. Now that
A. visit B. visited C. havevisited D. hadvisited
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