поезжай / езжай / ехай

In Russian, giving a command to 'go' by vehicle is a linguistic minefield because the base verb ехать does not have a standard imperative form (like едь). Instead, the language uses several variants depending on the social situation:

• Поезжай / Поезжайте: This is the only form considered correct in the literary standard for the simple command to 'go' by vehicle. It serves as the imperative for both ехать and поехать. (Note that the multidirectional verb ездить has its own imperative езди / ездите, and the verb for going on foot, пойти, uses пойди / пойдите). Etymologically, поезжай derives from the obsolete verb езжать, which explains its unusual stem.
• Езжай / Езжайте: This is extremely common in colloquial speech. While native speakers use it constantly, prescriptive grammarians classify it as informal or colloquial (разговорное). It is acceptable in everyday casual speech, though поезжай remains the strict literary standard.
• Ехай / Едь: These are considered 'illiterate' (просторечие). Using them is a strong social marker of low education. Avoid these in all professional or academic contexts.

Inclusive Imperative:
To say 'Let's go' or 'Let's drive', the most common and natural way is Поехали! You can also use the form едем / едемте.

The Prefix Rule:
A crucial rule for building fluency in Russian is that all prefixed derivatives of motion verbs ending in -ехать (such as приехать, заехать, or уехать) must form their imperative using the -езжай stem. For example:

• приехать → приезжай(те) (never приедь)
• заехать → заезжай(те) (never заедь)
• уехать → уезжай(те) (never уедь)

Negative Imperatives:
When telling someone 'don't go' (prohibition), the standard language switches to the multidirectional verb ездить. The correct form is не езди / не ездите. Saying не поезжай is considered a grammatical error in standard modern Russian because поезжай is almost never used with 'не'. Instead, Russian strictly borrows the negative imperative from ездить. However, note that prefixed verbs have standard imperfective partners ending in -езжать (e.g., уезжать, приезжать), and their imperatives DO take 'не' naturally (e.g., не уезжай, не приезжай).