[ Relative Clauses ]
The reason _____ he left is unclear.
A. who
B. that
C. whom
D. whose

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Grammar › ViewI ____ the movie last weekend.
A. watch
B. watching
C. watched
D. watches
Vocabulary › View
What is the process of thinking of solutions and problem solving called?
A. Feedback
B. Troubleshooting
C. Empowerment
D. Composure
