Read the following passage and choose the best answers.
The Butterfly People
A Canadian named Fred Urquhart loved monarch butterflies. But all the monarchs left when winter came. He wondered where they went.
In 1945, Fred married a woman named Norah. She loved butterflies too. “Where do butterflies go in winter?” they asked. To find out, they made special stickers. They put the stickers on many monarchs’ wings.
Many people found the butterflies in the south. They mailed them back to Fred and Norah. They also told Fred and Norah where they found the butterflies.
In 1976, Fred and Norah found the answer. They learned that monarchs fly over 4,000 kilometers south to Mexico in winter!
CÓ THỂ BẠN QUAN TÂM ________________________________