from English Grammar Today. We use if to introduce a possible or unreal situation or condition. We use when to refer to the time of a future situation or condition that we are certain of: You can only go in if you've got your ticket. When I'm older, I'd love to be a dancer. Compare.phrase. If you say that something will happen if necessary, when necessary, or where necessary, you mean that it will happen if it is necessary, when it is necessary, or where it is necessary. If necessary, the airship can stay up there for days to keep out of danger.
Merriam-Webster unabridged. The meaning of IF NECESSARY is if it is needed. How to use if necessary in a sentence.
1. Vaultboy2403. • 3 yr. ago. When necessary. Alaricos. • 3 yr. ago. Depends 1. IrishBard. • 3 yr. ago. As I'm sure you know, "when necessary" would normally focus on the time, "where necessary" on the place.
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