text: # -*- coding: utf-8 -*-
  
  n = int(input())
  
  # 2
  # Tpo oCder     TopCoder
  # aa bb         abab
  
  for i in range(n):
      a, b = input().split()
      ans = ""
  
      minimo = min(len(a), len(b))
      for j in range(minimo):
          ans += a[j]
          ans += b[j]
  
      for j in range(minimo, len(a)):
          ans += a[j]
  
      for j in range(minimo, len(b)):
          ans += b[j]
  
      print(ans)