【B17】
A. when
B. as
C. since
D. for
【B10】
A. have also invited
B. also had invited
C. also invited
D. had also invited
【B20】
A. amazed
B. amazing
C. amazingly
D. amazement
The tool for tattoo-making penetrates the skin ______.
A. by one million meters
B. by one centimeter
C. by one millimeter
D. by a million millimeters