I buy my mother a sweater.＝{#blank#}1{#/blank#}我给我妈妈买了件毛衣。

△sth若是代词，只能用buy sth for sb. 如：{#blank#}2{#/blank#}把它买给他。

We {#blank#}1{#/blank#} {#blank#}2{#/blank#} {#blank#}3{#/blank#} {#blank#}4{#/blank#}on our trip.

{#blank#}1{#/blank#}Mandy {#blank#}2{#/blank#}Susan likes this book.

My brother prefers clothes {#blank#}1{#/blank#} {#blank#}2{#/blank#} {#blank#}3{#/blank#}.

I hope you won't {#blank#}1{#/blank#} {#blank#}2{#/blank#} {#blank#}3{#/blank#} because of what I said.