A(2025·苏州)
without，mistake，such as，grow，in this way
新素材 科普知识 Hermit crabs(寄居蟹) are small animals that live in the ocean or on the beach. The crab has its own hard shell(外壳) but it only covers part of its body. The soft part cannot be protected 1. a shell. So the crab will find an empty shell and climb inside to stay safe.

As a hermit crab 2. ，it needs a bigger shell. Groups of hermit crabs gather to exchange shells. Sometimes, they fight over shells or line up to get the best one.
Hermit crabs eat just about any food they can find, 3. plants, dead fish or even food left on the beach. 4. ，they help keep beaches clean.
However，pollution can make it harder for hermit crabs to find real shells. Sometimes plastic bottles and caps are 5. for real shells. Once inside，many cannot get out and slowly die.
Beach cleanups，recycling，and using less plastic can make a big difference.

B
replace，happy，besides，relax，choose，train，sentence，complete，which，special
A green train in Southwest China has attracted much attention because of its own study room. The 1. train No. 5609/5610 runs between Chongqing and Xiushan County. In some carriages(车厢)，some seats have been 2. with desks and chairs to turn them into “study carriages” for passengers in need. The Chinese characters “Yu Yue” appear on the train，which means “travelling and reading 3. ”. Other encouraging 4. can be seen throughout the “study carriages”.
5. No. 5609/5610，other trains have also set up “study carriages”，including No. 5619/5620 and No. 5633/5634 which run along the Chengdu-Kunming Railway. Students from nearby schools often take the trains between school and home. The trains are their “school buses” and many students use their travel time 6. homework.
On train No. Z150，7. runs between Guiyang and Beijing，a “book bar” carriage has been welcomed by college students. There are nearly 400 universities and colleges in the cities along the line. And train No. Z150 is the first 8. for most students from those schools. Since 2015，the 9. dining car has been open for free at night to provide returning students with a lending library，free tea and other services. These small measures(措施) are a welcome comfort for passengers in need of a 10. place to continue their studies.