Question

sita-------(study) English for four years. (study,studied, is studying, was studying)

Answer 1

Here the parts of speech are the main thing along with the tense.

So it can be said Sita studied English for four years.

Sita is Studying English for four years, and Sita was studying English for four years.

They are past tense, present continuous tenses, and past perfect tense.

Answer 2

Sita is studying English for 4 years