A coordinating conjunction is a word that joins two elements of equal grammatical rank and syntactic importance.

They can join two verbs, two nouns, two adjectives, two phrases, or two independent clauses.

The seven coordinating conjunctions are for, and, nor, but, or, yet, and so.

Until indicates when something will happen, begin, or end.

Till means the same thing as until.

Till is not an abbreviation of until—it's actually older than until—and it should not be written with an apostrophe.

A word which connects words, clauses etc is called conjunction. 

Here that means   وہ  Because means کیوںکہ while unless means جب تک

We should plural noun or verb after using and.