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Millions of monarch butterflies (µÛÍõµû) once covered the trees of California’s coastal areas each winter, but now their numbers are decreasing.The recent annual Western Monarch Count found that the butterfly population was down by 99 percent from populations 40 years ago.

Monarch butterflies have two populations£ºeastern and western varieties separated by the Rocky Mountains.The populations are very similar in appearance, but western monarch butterflies are generally smaller and darker in color.The two also follow different migration (Ǩáã) patterns.Eastern monarch butterflies spend winter in Mexico, while western ones gather on central California coasts to wait out the cold.

In early spring, the two leave their rest places and begin to travel eastward.By the time the butterflies reach the Central Valley, they breed (·±Ö³)£®A butterfly can lay hundreds of eggs in a few weeks, and the new generation continues the migration.The cycle of generations and migration repeats every few weeks through the summer until the butterflies move as far as Idaho.And when the weather turns cold and the days get shorter, the butterflies return to California’s coasts.

The overwintering population was counted every year.The missing information is the time period when the butterflies leave their winter woods and begin to breed in February, March and April.“We just don’t know what they’re doing in that middle period and how we can better support the population£¬” said Washington State University biologist Cheryl Schultz.“Maybe they’re resting in the woods, or maybe they need more fuel along the way, etc.Any of those things might help monarch butterflies get from the coastal overwintering sites to breeding sites broadly in the Central Valley£¬” Schultz added.To fill that gap, the researchers set up the Western Monarch Mystery Challenge.

The ten­week program asks the public to submit photographs of monarch butterflies outside of their winter range.“We couldn’t be looking for monarch butterflies right now without the involvement of the community.There just aren’t enough of us£¬”Schultz said.“Reaching out to the community means we might be able to learn something where there is virtually no other way to learn it.”

1£®From Paragraph 1, we know monarch butterflies ______.

A£®are counted by researchers every decade

B£®are in a very difficult situation now

C£®have lost their home in California

D£®have moved to new places

½âÎö£ºÑ¡B¡¡ÍÆÀíÅжÏÌâ¡£¸ù¾ÝµÚÒ»¶ÎÖеēThe recent annual ... 99 percent from populations 40 years ago.”¿ÉÖª£¬µÛÍõµûÊýÁ¿Èñ¼õ£¬´¦¾³¿°ÓÇ¡£

2£®What do the two varieties of monarch butterflies have in common?

A£®Their breeding places.

B£®Their appearance and size.

C£®Their way of fighting against cold.

D£®Their migration destination in winter.

½âÎö£ºÑ¡A¡¡Ï¸½ÚÀí½âÌâ¡£¸ù¾ÝµÚÈý¶ÎÖеēIn early spring, the two leave their rest places ... they breed (·±Ö³)£®”¿ÉÖª´ð°¸¡£

3£®Why was the Western Monarch Mystery Challenge set up?

A£®To know the exact number of monarch butterflies.

B£®To help monarch butterflies get through tough winters.

C£®To know better about monarch butterflies to help them.

D£®To find out the influence of human activities on monarch butterflies.

½âÎö£ºÑ¡C¡¡Ï¸½ÚÀí½âÌâ¡£¸ù¾ÝµÚËĶÎÖеēThe missing information ... how we can better support the population”¼°×îºóÒ»¾ä“To fill that gap, the researchers set up the Western Monarch Mystery Challenge.”¿ÉÖª£¬ÊÇΪÁ˸üºÃµØÁ˽âËüÃÇÒԱ㱣»¤ËüÃÇ¡£

4£®What do Schultz’s words in the last paragraph show?

A£®It’s challenging to make the community get involved.

B£®It’s important to get help from the public.

C£®It’s difficult to study monarch butterflies.

D£®It’s rewarding to learn from the public.

½âÎö£ºÑ¡B¡¡ÍÆÀíÅжÏÌâ¡£¸ù¾ÝµÚÎå¶ÎÖеēWe couldn’t be looking for monarch butterflies right now without the involvement of the community ... virtually no other way to learn it.”¿ÉÖª£¬ÈôóÖÚ²ÎÓëµ½Õâ¸öÏîÄ¿À´ºÜÖØÒª¡£