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Phrasal Verbs

back up (2)

This page is about the phrasal verb back up (2)

Meaning

If you back up what you say, you use evidence or examples to show that it's true.

Synonym

support

For example

  • back sth up When making a claim, you should be able to use evidence to back it up.

  • back up sth They'll back up her story with photos, video clips and witness statements to prove that what she's saying is true.

  • back sth up with sth When writing an essay, you should state your main idea and then back it up with supporting evidence.

Nouns often used as objects with back up (2): claim, thesis, hypothesis, belief, contention, idea
back up with: evidence, examples, proof

Quick Quiz

If you accuse someone of doing something wrong, make sure you can back up what you say with

a. imaginative stories

b. detailed theories

c. strong evidence

Phrasal verbs grammar

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Contributor: Matt Errey