Generally Tense is classified into Present,Past and Future. In English each tense is further classified into:

1.Present Tense
Simple Present Tense, Present Continuous Tense,Present Perfect Tense and Present Perfect Continuous Tense.
2. Past Tense
Simple Past Tense, Past Continuous Tense,Past Perfect Tense and Past perfect continuous Tense.
3.Future Tense
Simple future Tense and Future perfect Tense

In future tense, I was told that there is no Continuous Tense and Future Perfect continuous Tense. Is it true? If so, why this is please explain.

Hi PP,

Not true: in the traditional system, those tenses also exist:

I will be studying Greek in Athens next summer.
I will have been studying Greek for 3 months when you arrive in Athens next summer.