Planul tarifar are roaming.

Because Romanian usually puts the definite article at the end of the noun.

• plan = plan / a plan
• planul = the plan

So planul tarifar means the tariff plan or the pricing plan.

In Romanian, adjectives often come after the noun.

• plan tarifar = tariff plan
• literally, this is plan tariff-related

That word order is the normal, neutral one in Romanian. Putting the adjective before the noun is possible in some cases, but it often sounds more marked, literary, or changes the emphasis.

Because in a normal noun + adjective phrase, the definite article is usually attached only to the noun, not to the adjective.

So Romanian says:

• planul tarifar = the tariff plan

not:

• planul tarifarul

The whole phrase is definite because planul is definite.

Because Romanian uses a avea = to have when talking about features, options, or included services.

So:

• are roaming = has roaming / includes roaming

Using este would not fit here, because the sentence is not identifying what the plan is; it is saying what the plan has.

Yes. In telecom language, Romanian very commonly uses the English loanword roaming.

You may see it in expressions like:

• are roaming
• include roaming
• servicii de roaming

In everyday commercial Romanian, this is very normal.

Yes, it is natural and understandable, especially in telecom, marketing, or customer-service contexts.

That said, Romanians might also say:

• Planul tarifar include roaming.
• Planul are roaming inclus.

These are very close in meaning. Are roaming sounds a bit like has roaming available/included.

You would usually use un:

• Un plan tarifar are roaming.

So:

• plan tarifar = a tariff plan or just tariff plan
• planul tarifar = the tariff plan

The plural is:

• planurile tarifare = the tariff plans
• au = have

So the full plural sentence would be:

• Planurile tarifare au roaming.

Breakdown:

• plan → planuri
• planul → planurile
• tarifar → tarifare
• are → au

A simple approximate pronunciation is:

• Planul → PLAH-nool
• tarifar → tah-ree-FAR
• are → AH-reh
• roaming → ROH-ming

So the whole sentence is roughly:

PLAH-nool tah-ree-FAR AH-reh ROH-ming

A few notes:

• r is usually tapped or rolled lightly.
• a is generally like the a in father.
• Romanian stress here falls roughly on PLA-, -FAR, A-, and RO-.