Grammar improvements: Originally, I will have a three-day vacation without any homework or pressures, but now, the competition cut half of the three days, cause I will be a volunteer.
The first day of the week is Monday.
The second day of the week is Tuesday.
The third day of the week is Thursday.
The fourth day of the week is Friday.
The fifth day of the week is Saturday.
The sixth day of the week is Sunday.
The seventh day of the week is Monday.
The eighth day of the week is Tuesday.
The ninth day of the week is Wednesday.
The tenth day of the week is Thursday.
I will have a three-day vacation without any homework, but I will have to work on the two-day vacation.

This is a very simple example of a simple sentence.

The first sentence is a simple sentence. The second sentence is a complex sentence. The third sentence is a complex sentence.

The third sentence is a complex sentence. The fourth sentence is a simple sentence.

The fourth sentence is a simple sentence. The fifth sentence is a complex sentence.