As long as, provided and providing are subordinating conjunctions. They express condition and are used at the beginning of a subordinate clause.
As long as | |
We use as long as to express a condition, i.e. to say that something will happen only on condition that something else happens. | I'll lend you the book as long as you promise to give me it back next week. (= If you don't promise to give the book back next week, I will not lend you it.) |
As long as expresses that one thing depends on another. | You can go to the party as long as you come back before midnight. (= You can go to the party, but you must promise to be back before midnight.) |
As long as has the same meaning asproviding orUNLESSUnless is followed by an affirmative verb to express "if ... not":My leg's broken. I can't stand up unless you help me. (I can't stand up if you don't help me.) provided. | You can go to the party providing /provided you come back before midnight. We're going skiing next week providing /provided there's enough snow. |