For this case, the first thing we must take into account is the time for which we are going to write the paragraph.
We note that the paragraph will be written in the present tense.
Therefore, any conjugation of the given verbs must be present.
We have then the following paragraph in Spanish:
Hoy Maria va a dormir tarde porque tiene un día bastante ocupado. Maria debe competir con personas de todos los países en la competencia internacional de matemáticas. Para poder ganar, Maria debe pensar mucho.
The translation of the paragraph in English is:
Today Maria is going to sleep late because she has a busy day. Maria must compete with people from all countries in the international math competition. In order to win, Maria must think a lot.
