For sewing pattern layout, folds are made along the grain line. Lengthwise center fold would be folding the fabric with selvages together. Crosswise centerfold is folding the fabric at the crosswise grain, that is along the weft threads from selvage to selvage.
the technical department checks the the stitching, seams, and that the garment is on grain. All the parts of the garment sewn should have the same grain. Sewing is done correctly, which type of thread and what count of thread to be used all this is taken care by the technical department while stitching a garment. hope the answer helped :)
Sewing
Straight line ending in arrowheads, means "place on straight grain of fabric."
NEEDLE
It is used to hold the bottom thread when sewing on a sewing machine
Sewing thread is used to hold together two pieces of a garment or really anything that you sew...
a seam
the tension is probably wrong. try tightening/losening it.
Baby lock
The pencil in sewing is called a "Marking Pencil".
A bobbin case is used for sewing on a sewing machine. It holds the bobbin in place so it is able to go in the sewing machine.