How can we make metatrader trade more than 1 pair at a time?

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I wrote this code and it is working, the problem is that it only trade one at a time, even though i have attached it on several pairs. Is it possible to make it trade on other pairs if those pairs reaches the criteria? Thank you.
 
Search forum for "semaphore" and see example
//+------------------------------------------------------------------+
//|                                                        trade.mq4 |
//|                      Copyright © 2006, MetaQuotes Software Corp. |
//|                                       http://www.metaquotes.net/ |
//+------------------------------------------------------------------+
#property copyright "Copyright © 2006, MetaQuotes Software Corp."
#property link      "http://www.metaquotes.net/"
 
#include <stderror.mqh>
#include <stdlib.mqh>
 
extern int ExtStopLoss=20;
extern int ExtTakeProfit=50;
 
string ExtTradeSemaphore="trade_semaphore";
//+------------------------------------------------------------------+
//|                                                                  |
//+------------------------------------------------------------------+
void init()
  {
//---- check for our semaphore
   if(GlobalVariableCheck(ExtTradeSemaphore))
     {
      int day_checked=GlobalVariableGet(ExtTradeSemaphore);
      if(day_checked!=0)
        {
         int semaphore_check=Day();
         //---- it may be wrong value in the our semaphore
         if(day_checked<semaphore_check-1 || day_checked>semaphore_check)
            GlobalVariableSet(ExtTradeSemaphore,0);
        }
     }
    else GlobalVariableSet(ExtTradeSemaphore,0); // semaphore created with "free" state
  }
//+------------------------------------------------------------------+
//|                                                                  |
//+------------------------------------------------------------------+
int start()
  {
   bool semaphored=false;
   int  ticket,error;
//----
   while(!IsStopped() && !IsTesting())
     {
      //---- check for zero value (free state) and occupate our semaphore with day number
      if(!GlobalVariableSetOnCondition(ExtTradeSemaphore,Day(),0))
        {
         if(GetLastError()==ERR_GLOBAL_VARIABLE_NOT_FOUND)
           {
            //---- create with "busy" state
            GlobalVariableSet(ExtTradeSemaphore,Day());
            semaphored=true;
            break;
           }
         //---- wait for half-second and check again
         else Sleep(500);
        }
      else { semaphored=true; break; }
     }
//----
   while(!IsStopped() && IsTradeAllowed())
     {
      //---- ask price may be changed when waiting
      RefreshRates();
      ticket=OrderSend(Symbol(),OP_BUY,1.0,Ask,3,Bid-ExtStopLoss*Point,Bid+ExtTakeProfit*Point);
      if(ticket<=0)
        {
         error=GetLastError();
         Print("Error = ",ErrorDescription(error));
         if(error==133) break;                          // trade is disabled
         if(error==134) break;                          // not enough money
        }
      else break;
      //---- 10 seconds wait
      Sleep(10000);
     }
//---- free our semaphore
   if(semaphored) GlobalVariableSet(ExtTradeSemaphore,0);
   return(0);
  }
//+------------------------------------------------------------------+
 
thank you so much for the feedback.
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