Which is a sentence fragment?
a) a crowd was drawn by a skateboarder doing flip tricks.
b) doing flip tricks, a skateboarder drew a crowd.
c) a crowd drawn by a skateboarder doing flip tricks.
d) a skateboarder doing flip tricks drew a crowd.

The answer is C

Explanation:

What is missing is a helping verb like "was" before the word drawn to make the sentence complete

i have heard the mermaids singing, each to each.

i do not think they will sing to me

the best practice

1. keep your workspace clean

2. wash your hands

3. seperate and clean chemicals and equipment

4.   use microfiber cleaning utensils

5. clean and sanitize all work surfaces

hope this !