Most verbs ending in -er conjugate as follows in Présent indicatif:
|new ending||jouer (to play)||visiter (to visit)|
|Je||-e||Je joue||Je visite|
|Tu||-es||Tu joues||Tu visites|
|Il/elle/on||-e||Il/elle/on joue||Il/elle/on visite|
|Nous||-ons||Nous jouons||Nous visitons|
|Vous||-ez||Vous jouez||Vous visitez|
|Ils/elles||-ent||Ils/elles jouent||Ils/elles visitent|
Note that the -er ending is replaced with new endings in each case.
The -es ending for tu and the -ent ending for ils/elles are written but NOT pronounced. When spoken they sound like joue.
You can listen to these conjugated forms of aimer to hear how they sound:
Here are more examples to listen to:
The infinitive of the verb is the unconjugated verb
-> jouer (to play) as opposed to a conjugated form like je joue (I play)
The stem of the infinitive is the part before the -er, -ir, -oir or -re ending.