Here are a couple of sentences that you may hear often and need to be able to respond to:

• Hay muchas cosas que escoger.
• Lo escogieron como su representante.

But a really good one you might hear in a restaurant, where a waiter (mesero) might say Escoge uno de los platos acompanantes, in which case you will need to choose something, say for example, two side items.

Notice the tricky thing about this verb?  In verbs such as escoger when you respond in the first person singular you must change the “g” to a “j” and then add the “o”. Other than first person singular, this verb is “regular”, eh, more or less (the present subjunctive is also a bit awry but we aren’t worrying about the subjunctive here). So you need to respond to el mesero by saying Escojo las papas fritas y ensalada. However, if you were speaking for everyone at your table you might say Escogemos las papas fritas y ensalada. If someone asks you tomorrow what you chose for your sides at dinner last night you could say, Escogi las papa fritas y ensalada or Escogimos las papas fritas y la ensalada.

The past participle of “escoger” is “escogido”.

The gerund is “escogiendo”.