They all carry many kinds of computers.
What would the correct present tense of carry be?
The present tense of carry is carry or are carrying.
When you refer to a verb, you refer to it by its present tense or infinitive form:
carry (present tense)
to carry (present tense)
It is understood that verbs have present, past, past participles that make up the "principal parts" -- that is, from these three parts, all forms of that verb can be formed.
carry, carried, carried
Regular verbs are referred to this way; their past tense endings are always -ed or -d.
go, went, gone
Irregular verbs are referred to this way; it's with the irregular verbs that troubles may arise!!