Is it permissible to give zakat to a person whose entire salary goes to pay off monthly debts (checks), and who borrows to cover his basic expenses? And are monthly checks considered a deferred debt?

The categories of zakat recipients are divinely ordained, and among them are the gharimin (debtors). Gharimin refers to those who have incurred debts not due to extravagance or squandering, or those who have undertaken debt to reconcile disputes (islaah dhaat al-bayn). A debtor is given from zakat if he is unable to repay his debt and has nothing to cover it, even if he is wealthy in the case of reconciling people. A reasonable presumption is sufficient for him to be considered among those eligible for zakat.