Is there as much water in this glass as in that one? Why is there used in this sentence? I know it's a sentence pattern be a as adj as, but why is there used

Is there as much water in this glass as in that one? Why is there used in this sentence? I know it's a sentence pattern be a as adj as, but why is there used

Is there means there is. Restore is & lt; there is & gt; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & nbsp; & lt; as & gt; & nbsp; & nbsp; & lt; much water & gt; & nbsp; (in this glass) & nbsp; & lt; as & gt; & nbsp; & nbsp