Whenever you come across a new verb, note what the ending is. Not as a memory task: just process it. "Hacer, -er verb, ok." Get into that habit, because once you know the ending you know how to work with the verb.
Hacer sounds like ha/th/er in most of Spain and ha/s/er in most of the Spanish-speaking world.
Hace · Lo hace · Lo hacen · Haces · Lo haces · Compro · Llego
The single most useful habit in this track. Before changing a verb, take one split second to identify it: "esperar, -ar verb." Otherwise your brain hears the /e/ sounds in espe- and wants to put an /e/ on the end, giving "espere" instead of espera.
esperar → espero, espera, esperan
Espero · Espera · Esperan · Me esperan · No me esperan · Quiero saber por qué no me esperan
For they are waiting for me you need no word for for. It is just they await me.
Puedo is I can or I am able, and it is an -er verb. It is related to power: when you can do something, you have the power to.
English says can you come, not "can you to come", but the to is what it means. That is an English quirk: it takes the to away sometimes, the same way it gives I must come rather than "I must to come". Think of it as I am able to come.
¿Puedes venir? · ¿No puedes venir? · ¿Por qué no puedes venir? · Quiero saber por qué no puedes venir
The d in the middle of a word is quite soft in Spanish rather than a hard /d/.
Apply the rule to salir and you get "salo". It is actually salgo, one of the same -go group you have already met.
Take any verb and apply the rule. Maybe it is irregular and you make a mistake, and that is the process working.
The student asks whether all these endings are not just memorisation after all. There is a difference between memorisation and remembering. You do need to remember Spanish, and you will remember it much more easily without the active process of trying to memorise, which blocks the very processes you need for remembering.
Address each part, apply all your mental energy to just that part, then forget it and move on.
English words ending -ary become -ario.
-ary → -ario
There is a grey area between v and b, and it shifts between languages. Vocabulario is spelled with a v but comes from boca, spelled with a b: your vocabulary is your "mouth-ulary". The same grey area explains saber against English savvy.
¿Qué haces? is literally "what are you doing?" and is also used to mean "how are you?" or "what are you up to?"
Two more words from this track: qué is what, and esperar carries both to wait and to hope, which is accurate enough given you are not doing much more than waiting when you hope. English has it in desperate: des- is un-, and you are hopeless when you are desperate.