Learn How to Crochet - Longer Basic Stitches
Double treble (dtr), triple treble (ttr) and quadruple treble (qte), etc., are made by wrapping the yarn over three, four or five times, etc. at the beginning and finishing as for a treble crochet, pulling yarn through two loops on the hook at a time until two loops remain on hook, and then pulling yarn through remaining two loops.
Learn How to Crochet - Making Crochet Fabric
To make a flat crocheted fabric worked in rows, you must begin with a starting chain. The length of the starting chain is the number of stitches needed for the first row of fabric plus the number of chains needed to get to the correct height of the first stitch used in the first row.
When working in rows, right-handers work from right to left and left-handers work from left to right, turning the work at the end of each row. One or more chains must be worked at the beginning of each row to bring the hook up to the height of the first stitch in the row. The number of chains used for turning will depend upon the height of the stitch they are to match.
Learn How to Crochet - Turning Chains
When turning a row, the first chain (turning chain) helps transition the row to the height of the first stitch of the new row. The height of the first chain (turning chain) must match the height of the first stitch, and the number of chains depends on the first stitch after the chain.
(1) single crochet = 1 chain
(2) half double crochet = 2 chains
(3) double crochet = 3 chains
(4) treble crochet = 4 chains
When working half double crochet or other taller stitches, the turning chain usually serves as the first stitch. The project instructions will let you know whether or not the turning chain is considered a stitch. When one chain is worked t the beginning of a row starting with a single crochet stitch, it is usually for height only and is made in addition to the first stitch.