11. What to do if the needle breaks due to many layers of cloth?

A. adjust tension B. set the needle property

C. tighten the presser foot

D. adjust pressure on the presser foot
12. What remedies applied to seam pucker if stitch length is too long?

A. Loosen tension screw.
B. Replace the needle.

C. Change the thread with correct thickness.

D. Adjust stitch regulator to normal stitch length.

13. Which of the following is a cleaning tool?

A. cotton buds
B. machine oil
C. record notebook
D. screw drivers

14. Which of the following is the correct sequence in cleaning the lower mechanism of the sewing machine?

A. remove dust, put oil, remove bobbin, return the parts
B. put oil, remove bobbin, return the parts, remove dust
C. remove bobbin, remove dust, put oil, return the parts
D. remove dust, remove bobbin, put oil, return the parts

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