针对joint liability，Investopedia给出的解释如下：

Joint liability denotes the obligation of two or more partners to pay back a debt or be responsible for satisfying a liability. A joint liability allows parties to share the risks associated with taking on debt and to protect themselves in the event of lawsuits. 

《元照英美法词典》给出的定义为“共同责任”，具体解释如下：

由两人或两人以上共同承担的责任，若其中一人被起诉，则其可要求其余人必须作为共同被告应诉；若其中一人死亡，则其责任由其他生存者承担。

作为joint liability的变体，Investopedia针对joint and several liability给出的解释如下：

Joint and several liability is a legal term for a responsibility that is shared by two or more parties to a lawsuit. A wronged party may sue any or all of them, and collect the total damages awarded by a court from any or all of them. If one party is unable to pay, the others named must pay more than their share. Joint and several liability tends to benefit the plaintiff, as it increases the chances that all of the damages awarded can be collected. On the other hand, it may be considered unfair to a party who bears only a minor responsibility for an adverse event to bear an outsized financial loss because of it.

《元照英美法词典》给出的定义为“共同的和个别的；连带的”，具体解释如下：

债务责任的一种形式。债权人可以选择分别起诉一个或数个债务人，也可以起诉全体债务人。如果某个债务人清偿了全部债务或超出其应清偿份额的债务，则其有权要求其他债务人分摊，如果某个债务人死亡，则可以用其财产清偿债务。在合伙的交易中，合伙人承担连带责任被认为是一种基本规则。

与joint liability正好相反，several liability表示“个别责任”，指两人或多人对原告的请求各自承担的责任（《元照英美法词典》）。

Investopedia给出的解释如下：

Several liability (or proportionate liability) is when all parties are liable for just their own respective obligations. An example would be if several business partners took out a loan for their business under the arrangement that each partner was responsible for their own share (severally liable). In such a case, if one partner did not meet their obligation under the loan, then the lender would only be able to sue the one partner for failure to meet their obligation.

从上述可知，由于每个人仅负责自己应付的债务，一旦有人未履行义务，债权人仅对该未履行义务之人进行起诉，而不会连累其他已履行义务之人。

例句：

1. 原文：After the Pledgee exercises the mortgage right in accordance with the Contract, if the collateral is not sufficient to pay off the guaranteed debts, and the Pledger is the third party other than the Borrower, the Pledger hereby promises to assume joint liability for the unpaid debts together with the Borrower.

译文：抵押权人按本合同规定行使抵押权后，如果抵押物尚不足以清偿担保债务而抵押人为借款人外第三人的，抵押人在此承诺对未获清偿的债务与借款人无条件承担连带责任。

2. 原文：After Co-borrower signs the Contract, Co-borrower shall enjoy same right and undertake same obligations with the Borrower under the Contract. Co-borrower shall undertake joint and several liability for the loan under the Contract.

译文：共同借款人在本合同上签字的行为即表示其与借款人在本合同下享有同等权利并承担同等义务，对本合同项下债务承担连带清偿责任。

3. 原文：Joint and several liability of the spouses is not created where one of the spouses takes on a loan or buys goods under hire purchase, in the event that this is not necessary to satisfy the joint needs of the family, without the consent of the other spouse.

译文：如果配偶一方不是为了满足家庭的共同需要，在未得到配偶另一方的同意下贷款或以分期付款的方式购买商品，则不产生配偶双方的连带责任。