Because the timing of injection is crucial, _____ mounted on the camshaft, which is driven
A. gears
B. rams
C. barrels
D. cams
【C5】
A. make for
B. take up
C. workout
D. lead to
Which of the following parental helps will the writer of Comment 3 consider proper？
Assisting kids in their exercises.
B. Making sure kids have finished their work.
C. Reviewing kids" homework for accuracy.
D. Monitoring kids" class performance.
【C2】
A. in place
B. in return
C. in person
D. in turn
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