Vietnamese countrymen, even when they are doing hard labor like pulling wood, pushing carts or rowing boats, can still think of and sing very romantic lyrics.

Thus, from hò to love songs is just a short step. Originally a form of dual love during work or rest, hò developed into ceremonial, festival songs in which boys and girls were divided into two groups to sing call-and-response or to sing competing for prizes.

As a result, hò could be divided roughly into three groups:
1.       During work, hò matches the actions of the work, rhythm and nonsense syllables (dô ta, rố khoan) are necessary.
2.       During rest, hò consists of songs for fun, dual love songs or simply love declaration songs.
3.       During festivals, hò includes call-and-response, calls for prizes.

Nonsense syllables in hò are very important because they bepeak the ryhtm of the work. Work calls are sung by many people. The main stanzas are always sung by one person (the mother or lead caller), whereas nonsense syllables are sung by the whole group (the children or chorus callers).

Work calls are divided into two categories: "inland" calls and "water" calls. Perhaps it is because boats were the only means of transportation in the old days that there is a preponderance of water calls.

The rố khoan rố khuầy of the North is a water call with strong rhythm. During long trips transporting passengers from one province to another, oarsmen row the boat in turns and sing this call-type to reinforce themselves:

Husband and wife and even the child
We all try to catch the fish,
This river is so immense
We can’t see where the wharf is.

The word khuầy signifies the action of stirring water. The chorus, when singing this word, stirs water to push the boat onward.
Water calls sometimes go a step further than work calls, becoming rest calls. This gave birth to a new love call-type: Hát đò đưa. Hát đò đưa then became dual love songs in music diversion and music of the popular theater:
The wind blows
and strikes the boat away,
Why have you kept yourself undecided for so long.
The wind blows
and strikes the vông tree,
May I ask you if you want to get married.
The wind blows
and strikes the sycamore tree,
I agree to get married but I won't share the bed with my husband.
The wind blows
and strikes the boat away,
As a matter of fact, I don't care whether water flows or the boat leaves....