du/de la vs à la/au.
- Ma fille veut faire de la natation à la rentrée
- Étienne joue au tennis le samedi matin.
Looking at the above two sentences, I am completely confused about the usage of du/de la vs à la/au.
In what situations we use which?
When talking about sports in French, "faire" is followed by "de" and "jouer" is followed by "à".
There's an explanation of how to talk about different sports here: https://www.thoughtco.com/french-vocabulary-learn-to-talk-sports-4079654 (scroll down to The French Verbs Used With Sports)
When writing prepositions in French, the preposition and "le" often contract to a single word. However, the feminine version typically keeps the preposition and the article (la).
de: de+le is du; de+la is de la; de+l' is de l'; de+les is des
à: à+le is au; à+la is à la, à+la is à la; à+les is aux
I hope this was helpful to you.