Emphatic do & auxiliaries

Rules

• Rule 1: do / does in the present

  Normally we don't use *do* in a positive present simple sentence. For emphasis we add do (I / you / we / they) or does (he / she / it). The verb stays in the base form; the *-s* moves to does.

  Pattern: subject + do / does + base verb

  Example: We do want to help.

  Example: My cat does sleep a lot!

• Rule 2: did in the past

  In the past simple we use did + base verb with every subject. The *-ed* or irregular past form disappears, because did now carries the past.

  Pattern: subject + did + base verb

  Example: She did finish the book.

  Example: I did see a fox in the backyard!

• Rule 3: Do in imperatives

  Putting Do in front of an imperative makes it warmer and more insistent: an invitation or a heartfelt request. It works with *be* too: Do be quiet.

  Pattern: Do + base verb …!

  Example: Do come to my party!

  Example: Do be careful with the glasses.

• Rule 4: No do with be, have and modals

  If the sentence already has an auxiliary (am / is / are / was / were, have / has in the present perfect, can / will …), we don't add *do*; we stress that auxiliary. In short answers the stress also falls on the auxiliary: *I really do!*

  Pattern: subject + AM / HAVE / CAN … (stressed)

  Example: “You aren't trying.” “I am trying!”

  Example: “You can't ride a bike.” “I can!”

Common mistakes

• She does speaks French. → She does speak French.

  After does, the verb is base form; no double *-s*.

• I did called you. → I did call you.

  After did, use the base form.

• I do am listening. → I am listening.

  No *do* with be; stress *am* instead.