For all these patterns, I used a size 10 (bedspread) cotton crochet thread and a steel size 7 (1.5 mm) crochet hook.

Stitches used in US terms
Ch/ch--------------chain
Hdc/hdc-----------half double crochet
Sc/sc---------------single crochet
Sk/sk---------------skip
Sl st/sl st-----------slip stitch
Special Stitches
BegCs-------------beginning Closed Shell (ch 3, 2dc, in same space)
BegOs-------------beginning Open Shell (ch 3, 1 dc, ch 1, 2 dc, in same space)
Cls-----------------closed Shell (3 dc, in same space)
Os------------------open Shell (2dc, ch1, 2dc, in same space)

Stitches used in UK terms
Ch/ch--------------chain
Htr/htr------------- half treble crochet
Dc/dc---------------single crochet
Sk/sk---------------miss
Ss/ss----------------slip stitch
Special Stitches
BegCs-------------beginning Closed Shell (ch 3, 2tr, in same space)
BegOs-------------beginning Open Shell (ch 3, 1 tr, ch 1, 2 tr, in same space)
Cls-----------------closed Shell (3 tr, in same space)
Os------------------open Shell (2tr, ch1, 2tr, in same space)