Do vs. Did

Congratulations to Barack Obama who will become the 44th President of the United States on January 20th! We're lucky to have him as our next leader.

In Lesson Three in the Red Level, look at the difference between "do" and "did." They're both helping verbs, but one is used for the present tense (do) and the other is used for the past tense (did). If you understand that, and you understand how to use the simple form of the verb, you will develop very good control over your use of English.

Examples:

What do you eat for breakfast every day? (present tense: do + eat)

What did you eat for breakfast yesterday? (past tense: did + eat)

In both examples above, "eat" is in the simple form (eat/ate/eaten), and the helping verb determines the verb tense.