The question makes no sense. For one thing, Velcro and Swiss engineers are not mentioned in the text. Also, answer 5 is not grammatical.
Student or Learner
The answer is 3, which is weird. The question maker argues that mussel glue doesn't have self-reparing ability, but the passage definitely shows it like the underlined. Don't "it" and "itself" all refer to "glue" not "mussels"?
How do mussels stay attached (B)[to / on] rocks despite the extreme force of the sea? They produce their own self-sticking glue. It repairs ⓒitself when the mussels ⓓare washed away by waves and sand. Scientists still do not entirely understand how the natural glue works. ㉡___________ they have figured out ⓔhow to copy this substance in a man-made version. It can be used for a number of things, such as coating (C)[for / with] underwater machinery or a medical glue.....
10..① Velcro was invented in 1940 and it has a number of small hooks. ② Swiss engineer examined the burrs adhering to his pants through a microscope. ③ Mussel glue has a feature of self-repair ability when mussels are damaged by waves and sand. ④ Until now, there is no clear explanation of how the natural glue works. ⑤ Scientists don't figure out a clear principle of the mussel glue, but they copied its feature.Which of the following is NOT true?1)
Last edited by keannu; 20-Apr-2014 at 02:30.
Why doesn't this work? Does it have to be "Scientists haven't figured out a clear principle"?
5. Scientists don't figure out a clear principle of the mussel glue, but they copied its feature.