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Re: Imperative
by Greg Brush - Thursday, 29 December 2016, 08:35 PM
  First, a comment on terminology:
To avoid potential confusion for other students, I'll use the LGO terms and call your "Imperative Present" the continuous (or imperfective) imperative and "Imperative Aorist" the non-continuous (or perfective) imperative.

As to your question, Greek is similar to Spanish in that:
a) Positive commands for 2nd person use the true imperative; positive commands for 1st or 3rd person are normally formed with να or ας + subjunctive, either continuous or non-continuous depending (in theory) on the aspectual context of the action.
b) Negative commands in Greek for all three grammatical persons (1st, 2nd, and 3rd) are formed with μη(ν) + subjunctive, again either continuous or non-continuous depending (in theory) on the aspectual context of the action.

So in your examples, the positive commands for "we" are:
να (or ας) δούμε τηλεόραση!
να (or ας) πάμε! (or commonly simply πάμε!)

The negative commands are:
να (or ας) μη δούμε τηλεόραση!
να (or ας) μην πάμε! (or simply μην πάμε!)

Lesson 60 introduces commands & prohibitions (both continuous & non-continuous) of active stem-stressed verbs; Lesson 100 presents the imperative (continuous & non-continuous) of active end-stressed verbs. LGO does not, however, mention the imperatives of either stem-stressed or end-stressed verbs in middle/passive voice.

Regards,
Greg Brush