How to insert a variable into a string

For example, how to insert a variable into a string? $ s & nbsp ;=& nbsp ;$ _ GET [& quot; word & quot;]; echo & nbsp; & quot; how does your & nbsp; word & nbsp; is & nbsp insert variables into strings?
For example,

$ S = $ _ GET ["word"];
Echo "your word is $ s ";

There is no problem with running the above code, but it won't work if it is changed to this:

Echo 'Your word is $ s ';

Don't use '', but the actual situation is that sometimes'' is required. for example, if I want to output link, because "" is used in html, so in order to avoid inserting too many \ S, php will use print ''to output. how can we solve the problem of inserting variable strings?

I can use printf to solve the problem, but it is always very troublesome. Is there a simpler way, just like inserting string variables in?

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Echo 'Your word is {$ s} '; --> echo "your word is {$ s }";
What is in single quotes is output.
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If you want to use single quotes
Then replace the eval or character
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Check this function ~~~
Eval