Choose the option opposite in meaning to the underlined word or phrase. The dressmaker unpicked the seam of the shirt.
Answer Details
The option opposite in meaning to the underlined word "unpicked" is "sewed up".
When you "unpick" a seam, it means you are removing the stitches that were previously sewn, and essentially taking the fabric apart. On the other hand, "sewing up" refers to the act of putting things back together by sewing or stitching them. So, if the dressmaker "unpicked" the seam of the shirt, it means that she was taking it apart, but if she "sewed up" the seam of the shirt, it would mean she was repairing it or putting it back together.
In simpler terms, the sentence means that the dressmaker was removing the stitches of the shirt's seam.