title: assembly error: "instruction operands must be the same size"
body: <p>I'm very new at this and I'm trying to move values from one array to the other,
  it suppose to be:</p>
  
  <pre><code>vec1 = 1, 2, 3, 4, 5
  vec2 = 5, 4, 3, 2, 1
  </code></pre>
  
  <p>but I get an error: "instruction operands must be the same size"</p>
  
  <pre><code>TITLE program
  
       .386
       .model flat
       extern _ExitProcess@4:Near
       .data
  
       vec1 WORD 1, 2, 3, 4, 5; original array
       vec2 WORD 5 DUP(?)
       .code                 
  _main:
  
      mov ebx, 0
      mov ecx, lengthof vec1
      DO:
      mov eax, vec1[ebx]
      mov vec2[ecx], eax
      inc ebx
      loop DO
  
      push    0                       
      call    _ExitProcess@4          
  
      end   _main       
  </code></pre>
  
  <p>please help.</p>