Use "both" when testing membership for 2 things

spec.html

@@ -48924,7 +48924,7 @@ <h1>Relations of Candidate Executions</h1>
       <h1>is-agent-order-before</h1>
       <p>For a candidate execution _execution_, its <dfn>is-agent-order-before</dfn> Relation is the least Relation on events that satisfies the following.</p>
       <ul>
-        <li>For events _E_ and _D_, _E_ is-agent-order-before _D_ in _execution_ if there is some Agent Events Record _aer_ in _execution_.[[EventsRecords]] such that _E_ and _D_ are in _aer_.[[EventList]] and _E_ is before _D_ in List order of _aer_.[[EventList]].</li>
+        <li>For events _E_ and _D_, _E_ is-agent-order-before _D_ in _execution_ if there is some Agent Events Record _aer_ in _execution_.[[EventsRecords]] such that _aer_.[[EventList]] contains both _E_ and _D_, and _E_ is before _D_ in List order of _aer_.[[EventList]].</li>
       </ul>
 
       <emu-note>
@@ -48951,7 +48951,7 @@ <h1>reads-bytes-from</h1>
       <h1>reads-from</h1>
       <p>For a candidate execution _execution_, its <dfn>reads-from</dfn> Relation is the least Relation on events that satisfies the following.</p>
       <ul>
-        <li>For events _R_ and _W_, _R_ reads-from _W_ in _execution_ if SharedDataBlockEventSet(_execution_) contains _R_ and _W_, and reads-bytes-from(_R_) in _execution_ contains _W_.</li>
+        <li>For events _R_ and _W_, _R_ reads-from _W_ in _execution_ if SharedDataBlockEventSet(_execution_) contains both _R_ and _W_, and reads-bytes-from(_R_) in _execution_ contains _W_.</li>
       </ul>
     </emu-clause>