Sweep vs. swipe?

English Language Tests, Intermediate level

ESL/EFL Test #677 [color=blue]“English Slang Idioms (419)”, question 2

“My sister’s always complaining that she doesn’t have a boyfriend, but she never accepts dates. I doubt a boy is going to just come to our house and her off her feet,” Marilynn said to Elsa.

(a) swing
(b) sweep
(c) swipe
(d) snatch

English Language Tests, Intermediate level

ESL/EFL Test #677 [color=blue]“English Slang Idioms (419)”, answer 2

“My sister’s always complaining that she doesn’t have a boyfriend, but she never accepts dates. I doubt a boy is going to just come to our house and sweep her off her feet,” Marilynn said to Elsa.

Correct answer: (b) sweep
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What is the difference between swipe and sweep? I thought they were synonyms?

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The action is similar, but that is all. The idiom here is ‘to sweep one off one’s feet’.
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