# Chain

In syntax, a **chain** is a set of syntactic elements subject to specific conditions.

Formally:

(a^{1},...,a^{n}), 1 =< n, is a chain iff (i) everyahas the same subscript, i.e (a^{1},...,a^{n}) = (a_{j}^{1},...,a_{j}^{n}) (ii) for every i < n, a^{1}antecedent-governs a^{i+1}

Given this definition a^{1} is called the *head* of the chain, an the foot, and each pair (a^{1},a^{i+1}) is a link. The superscripts only serve to distinguish elements which are otherwise identical; so, superscripts are left out in the notation if the elements are not identical. Different kinds of chains are distinguished. A chain is an A-chain if a^{1} is in an A-position, and an A-bar-chain if a^{1} is in an A-bar position.

### Examples

In (i) both (*John*_{i}, t_{i}) and (*the car*_{j}) are A-chains. The chain (*John*_{i}, t_{i}) consists of one link, *John*_{i} being the *head* and t_{i} being the *foot*. The chain (*the car*_{j}) has no link, and *the car*_{j} is both its head and its foot.

(i) John_{i}was hit t_{i}by the car_{j}(ii) Who_{i}ti^{1}seems t_{i}^{2}to have been hit t_{i}^{3}by the car_{j}

In (ii), the chain (*who*_{i}, ti^{1}, t_{i}^{2}, t_{i}^{3}) is an A-bar-chain, since the head *who*_{i} is in an A-bar-position. The foot (i.e. t_{i}^{3}) of this chain is theta-marked (by *hit*). The element t^{1} is case marked (by the matrix INFL). Hence, the chain satisfies the case filter and the theta criterion. The A-chain (t_{i}^{1}, t_{i}^{2}) is an example of a non-maximal chain, since this chain, being part of the maximal chain (*who*_{i}, t_{i}^{1}, t_{i}^{2}, t_{i}^{3}) contains no theta-position.

### Comment

Grammatical properties, such as theta-roles and Case visibility (visibility condition) are properties of maximal chains. A chain is maximal if it contains a theta-position. In general, maximal chains are simply called chains.

### Link

Utrecht Lexicon of Linguistics

### See also

### References

- Chomsky, Noam A. 1981.
*Lectures on Government and Binding.*Dordrecht:Foris. - Chomsky, Noam A. 1986.
*Knowledge of language: its nature, origin and use.*Praeger, New York.