Is the phrase push or pull through, interchangeable regarding the words push and pull? Is one word more grammatically correct than the other?
Depends on the statement you are emphasizing on, 'push through' and 'pull through' are both phrasal verbs.
Note: A phrasal verb is a phrase consisting of a verb and either or both of a preposition or adverb that has idiomatic meaning. Such as your examples 'pull through' and 'push through'; 'push' is a verb and 'through' could be adverb or preposition. It depends on the statement.
The president is trying to push through various tax reforms.
I'm glad he pulled through.
Meaning: "To survive something"
There is no grammatical difference between them, but they have different meanings.
When used literally, pushing is applying force from behind to press something through a gap; pulling is applying force from the front to draw it through.
If you're using them figuratively, it is possible that they will both do in some context: it depends on the context.
As idioms, they have specific meanings that are not interchangeable: "push something through" means to work to get it accepted or approved, or voted on. "Pull through" (intransitive) means to survive an illness or injury.
Depends on the statement you are emphasizing on, 'push through' and 'pull through are both a phrasal verb' Note: A phrase consisting of a verb and either or both of a preposition or adverb, that has idiomatic meaning. In your examples pull through and push through, push is a verb and through could be adverb or preposition. It depends on the statement.
e.g: The president is trying to push through various tax reforms.
Meaning: "To cause a plan or suggestion to be officially accepted or put into use:"
e.g: I'm glad he pulled through.
"To survive something".
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