The verb to do is used in a number of different ways in English. Here are the main uses of the verb to do for reference, self-study and in-class use. To do can be used as an auxiliary verb, a verb to speak about action in general, as well as combining with many nouns to express taking care of various tasks.
To Do - Main Verb
To do is used as a principal verb in many set phrases used with the various tasks we do around the house and at work. To do is generally used to express tasks we do, rather than things we make. Of course, there are some exceptions to the rules. Here are some of the main set phrases about tasks we do:
do the dishes
do yard work
I'll do the dishes if you make dinner.
Sheila tries to do sport at least three times a week.
He's done that exercise a number of times.
NOTE: To do exercise is used with a number of different types of exercise. Generally, we use 'play' with competitive sports, 'go' with activities such as walking, riding, and hiking. 'Do' is used with exercises such as yoga, karate, etc.
Jennifer did yoga for two hours this morning.
I try to do some exercises like sit-ups and push-ups every morning.
James does pilates at his local gym.
To Do - Auxiliary Verb
To do is also used as an auxiliary verb in the simple tenses. Remember that the auxiliary verb takes the conjugation in English, so the verb to do will change depending on the tense. Remember that 'to do' is used as an auxiliary verb only in the question and negative form. Here is a quick review of the tenses that use to do as an auxiliary verb:
She doesn't like tofu.
Do you enjoy rock 'n roll?
Mary didn't visit her aunt last week.
Did they talk about the economy?
To Do - General Use Verb
To do is used as the main verb when asking general questions about what happens, is happening, is going to happen, etc.
What are you doing?
What will you do?
What have they done?
What do you do on Saturdays?