invisible decrease (dec)

To do a invisible decrease stitch. The decrease means combining 2 stitches into 1 stitch.
  We just insert the front loop only in the next stitch, we don't do a yarn over but continue to insert the front loop only in the next stitch.
   Now we have 3 loops on the hook, we do a yarn over and through the first 2 loops. There are 2 loops left on the hook. Do a yarn over and through these 2 loops. The decrease stitch finish.
  Do it again…… It's called decrease.

Video

①

We just insert the hook into the front loop only in the next stitch.

②

We continue to insert the hook into the front loop of the next stitch.

③

Now we have 3 loops on the hook, we do a yarn over and through the first 2 loops.

④

There are 2 loops left on the hook.

⑤

Do a yarn over and through these 2 loops.

⑥

There 1 loop left on the hook. An invisible decrease stitch finish.