DCDR and VCDR
Dec. is the correct abbreviation
Ave.
Both are correct. "Do" is an auxiliary verb.
correct
The correct spelling is auxiliary (assisting or supporting, or an assisting device or group).
Your spelling is correct
Because when you use an auxiliary, the verbs are always normal. Because the auxiliary is passing the sentence to the correct tense form.
An auxiliary verb.
There are no "correct" abbreviations for birds. The first syllable usually works: car.
No, "go" is not an auxiliary verb in that context. It is being used as a main verb to show an action or movement. Auxiliary verbs usually accompany main verbs to form a complete verb phrase.
Have done is correct. When using have as an auxiliary verb, it's paired with a past participle.
That is the correct spelling of the noun "division" (dividing).