Hiệp này bắt đầu rồi.

Hiệp usually means a round, half, period, or bout, especially in sports, games, or fights. The best English word depends on the context.

For example:

• in soccer: half
• in boxing or martial arts: round
• in some games: period or round

So hiệp này means this round/half/period.

In Vietnamese, words meaning this and that usually come after the noun.

So:

• hiệp này = this round
• hiệp đó / hiệp kia = that round

This is normal Vietnamese word order.

Bắt đầu means to begin or to start.

In this sentence, it is the main verb:

• Hiệp này = this round
• bắt đầu = start / begin

So the sentence is built very simply: This round + start + already.

Here, rồi shows that the action has already happened or that a new state has been reached.

So bắt đầu rồi means:

• has started already
• has begun
• is now underway

It often gives a sense of before, it had not started; now it has.

Vietnamese does not use helper verbs the same way English does. It often does not need words like is, has, or has been.

Instead, Vietnamese uses:

• the main verb
• context
• aspect words like rồi, đã, đang

So Hiệp này bắt đầu rồi naturally means something like This round has started already, even though there is no separate word for has.

Because rồi already makes it clear that the starting has happened.

These are all possible:

• Hiệp này bắt đầu rồi
• Hiệp này đã bắt đầu
• Hiệp này đã bắt đầu rồi

The differences are small but real:

• bắt đầu rồi: very natural; focuses on the fact that it has now started
• đã bắt đầu: neutral statement that it started
• đã bắt đầu rồi: stronger emphasis on already

Yes. Hiệp này functions as the subject-like noun phrase: this round.

So the sentence breaks down like this:

• Hiệp này = this round
• bắt đầu rồi = has already started

Vietnamese does not need an extra pronoun like it.

Yes, depending on context and tone of voice.

Besides the basic meaning, it can imply things like:

• It’s started already, so hurry up
• The round is already underway
• You’re late
• Pay attention, it has begun

That extra feeling comes from the situation, not just from the grammar.

No. Hiệp itself is already a unit noun, so hiệp này is fine as it is.

Vietnamese often uses classifiers with many nouns, but not every noun needs one in every structure. Here, hiệp này is the normal way to say this round.

Usually, Hiệp này bắt đầu rồi is more natural if you mean it has started.

Đang means something like in the process of, so đang bắt đầu would mean is starting and may sound a bit less natural in many everyday contexts. People usually prefer:

• bắt đầu rồi = has started already
• sắp bắt đầu = is about to start

So if the round has already begun, Hiệp này bắt đầu rồi is the better choice.