7.3 Verbs.

Tense indicates the time relation of a verb: present (I am), past (I was), future (I will be), present perfect (I have been), past perfect (I had been), and future perfect (I will have been). It is important to choose the verb that expresses the time that is intended. It is equally important to maintain consistency of tense.The present tense is used to express a general truth, a statement of fact, or something continuingly true.He discovered enzymes RNA polymerases that directly copy [not copied] the messages encoded in DNA.For this reason, the present tense is often used to refer to ...Less