Question

He __________ in the States but he still does not have a command over the English language

Answer 1

Answer:

He has been living in the States but he still does not have a command over the English language.

Explanation:

We use the present perfect continuous for an action over a period of time leading up to specific time. We also use 'for' and 'since' with the stated time period or duration.  

The verb form for this tense is:

has/have+been+V1+-ing

Answer 2

Answer:

He has been living in the States but he still does not have a command over the English language.

has been living