French Verbs: Aller Venir

The pattern to express near future or near past:

Subject	aller / venir de	verb	complement
Mes parents	vont	venir	chez moi
Le nuage	vient de	cacher	le soleil

The French verbs aller and venir are often used as auxiliary verbs to express the near future (aller) and the near past (venir de).
Note that the second verb is always in the infinitive. (Reminder: the infinitive is the "flat" form of a verb; it bears neither person nor tense.)
When 2 verbs follow each other, the second one is always in the infinitive (if the first one is neither être nor avoir).
Though "venir d'aller" asks for specific situations, "aller venir" (I am going to come) is common.

Où: where
Quand: when.
You can ask questions, either by inverting the subject and the verb: Où vas-tu?
or by adding est-ce que between the asking word and the affirmative sentence:
Où est-ce que tu vas?

NB: despite the varied spellings (-e, -es, -ent), there are only 3 oral endings in the conjugation of regular -er verbs (regular -er verbs: all -er verbs except aller.)

Quand mes petits-neveux viennent, je retrouve mes 20 ans.

je trouve (I find, I discover), je retrouve (I find what has been lost)
tu trouves, tu retrouves
il trouve, il retrouve
nous trouvons, nous retrouvons
vous trouvez, vous retrouvez
ils trouvent, ils retrouvent