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Every year, butterfly(蝴蝶) lovers in California go out in November to count
monarch butterflies. They {#blank#}1{#/blank#}(get)
a worrying result from their fall monarch count in 2018—{#blank#}2{#/blank#} number of monarchs had dropped by 86% since 2017.
The orange and black monarch butterflies are famous {#blank#}3{#/blank#} their long migrations(迁徙)—they fly thousands of miles every year. In the spring and summer they fly north; in the fall they fly south again.
Monarchs, like most butterflies,
are {#blank#}4{#/blank#}(terrible) important for
plants. They help create more plants by spreading pollen(花粉) between plants. In turn, monarchs depend on plants
for food. And they depend completely on a plant called milkweed {#blank#}5{#/blank#}(lay) their eggs.
But monarchs have been facing
growing problems for years. As more and more wild land has been turned into large
farms, the monarchs have had trouble {#blank#}6{#/blank#}(find) enough milkweed. Many farms also
use chemicals {#blank#}7{#/blank#} will kill insects in order to protect their plants.
These chemicals also affect monarchs. Besides, pollution has made milkweed less
{#blank#}8{#/blank#}(health) for the monarchs
than it used to be.
Scientists say monarchs will
be in danger of dying out in the next 20 years if nothing {#blank#}9{#/blank#}(do) to save them.
{#blank#}10{#/blank#}(thing) that people can do to help include
planting milkweed, controlling the use of chemicals, protecting wild areas, and
planting trees.
