x1=p1=b2 uses language / language feature / complete language / language dialect or variation / dictionary / semantics / other language standard or specification or open source fork x2=p2=b1 with scope / for text / purpose / to express / communicate x3=p3=b3; x1 is using / declaring language / language extension x2.
x1=k1 (event) is the instance/recurrence/repetition of x2=t1 [agent] reading x3=t2 [text] from surface/document/reading material x4=t3 for the x5=k3rd time; x2 re-reads x3 from x4.