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if necessary is the most popular phrase on the web.

if needed 160,800,000 results on the web	if necessary 180,600,000 results on the web More popular!
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It doesn't look like this phrase is very popular! The search could not find any examples on the internet.	Lieutenant, prepare to counterattack Pork Chop if necessary. Laws can be changed if necessary, Dumbledore. All next winter, if necessary. When adopting Decision 1999/815/EC it was foreseen to prolong its validity if necessary. The budget may be increased for subsequent years if necessary. Water can be replaced if necessary. The Committee shall appoint rapporteurs to examine these investigations and, if necessary, issue an opinion. You mention changing the criteria, if necessary.

if needed

160,800,000 results on the web

if necessary

180,600,000 results on the web

More popular!

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

Lieutenant, prepare to counterattack Pork Chop if necessary.
Laws can be changed if necessary, Dumbledore.
All next winter, if necessary.
When adopting Decision 1999/815/EC it was foreseen to prolong its validity if necessary.
The budget may be increased for subsequent years if necessary.
Water can be replaced if necessary.
The Committee shall appoint rapporteurs to examine these investigations and, if necessary, issue an opinion.
You mention changing the criteria, if necessary.