The sign for "chain" is based on the "connect" sign (which also means such things as "of," "join," "member of," and "link.")
CHAIN / links / Olympics:
Notes:
In normal everyday usage in a sentence signed between two fluent adults you only use "two" links (or "two" movements"). Sometimes you might see this sign done with three links but generally three links would be used only on first reference to introduce the topic to the conversation. For example, visualize an elementary school teacher getting the attention of her students and then excitedly signing "We are going to make a paper chain today!" (TODAY MAKE PAPER CHAIN!) Upon second reference there would be no point in wasting the effort to make three movements.
Also see: FENCE
Also see: CONNECT
Notes: