About the problem of variable $foo in "" quotes in Linux

Now we get an incoming parameter from the command line $1, assuming the value of $1 is 666
We want to use $1 in sed -i, assuming the command is sed -i " s/foo/$1/g” file.txt
Now we need to write an ant build.xml (can be understood as a script), and we need to implement the sed instruction:

<exec executable="/usr/bin/sed" dir="common/self_cleaning_builder">
    <arg line="#我需要的那条sed指令"/>
</exec>

我应该如何把这个sed指令放入arg标签下的line=“”中，才能使得我放进去的指令可以被正确读出且实现功能？引号太多了，怎么写都实现不了功能。

What I wrote is:

<exec executable="/usr/bin/sed" dir="/common">
    <arg line='-i -r "s/foo//g" file.txt'/>
</exec>

as well as

<property name="regex" value="s/input//g"/>
<exec executable="/usr/bin/sed" dir="/common">
    <arg line="-i -r $regex file.txt"/>
</exec>

But none of them can achieve the function I want.

After reading some posts about “” and ‘”, I still don’t know how to solve this problem. I hope you can give me some advice