I was instructed never to do clothing with embroidery thread. It is not strong enough to hold your normal wear and tear that we put on our garmets.
IF it is all you have available and it matches the fabric I would use it. Not for hems where it will be noticeable (shine). I would set my machine for a closer stitch so there isn't a possibility that it can pull.
not usually. This thread is of a lighter weight and therefore not as strong as regular sewing thread. you may have an 'oopsie' ;-)
Monica, I guess you could use them - however - because they are thicker and with the shine on them - they could show up much more than regular thread - but if you were in a pinch and needed something that color and you didn't have any - it could work for you.
Yes, you should - if you are going to be sewing - I would highly suggest doing so. You can sometimes find a great deal on sewing thread at your local fabric store or buy some online - they have packages of them on sale all the time.