Sentence:  But for all the manifest intention to `` show off '' , this was a circus with a difference , for instead of descending in quality to what is known as a popular level , it <WSD>added</WSD> further to the evidence that this is a very great dancing company . 
Meaning of the word marked with <WSD> tags:  make an addition (to); join or combine or unite with others; increase the quality, quantity, size or scope of