Irregular Verbs kuru and suru

Did something seem amiss with the last example in Lesson ? I hope so, because it means you noticed that while kuru looks like a yodan verb, it conjugated like an ichidan. It is now time to introduce the irregular verbs kuru and suru.
We have already practiced using yodan and ichidan verbs. Besides these are the irregulars, but the good news is that there are only two: kuru, which means "to come"; and suru, which means "to do." These two have their own set of rules when it comes to conjugating, but since both are used frequently they can be mastered quickly and naturally.
The Base 2 form of kuru is just ki. Let's use it to review some of the endings already learned:

• Bob wa kimasu. (Bob will come.)
• Sue wa kimasen. (Sue won't come/won't be coming.)
• John wa kimashita. (John came.)
• Ken wa kimasen deshita. (Ken didn't come.)
• Yumi wa kitai desu. (Yumi wants to come.)

Suru is not only a handy "stand alone" verb, but is also used to make countless nouns into verbs: benkyou suru (study), shimpai suru (worry), chuumon suru (place an order), yakusoku suru (promise). The Base 2 form of suru is shi. Look at these examples:

• Watashi wa shimasu. (I'll do it.)
• Kare wa shimasen. (He won't do it.)
• Bill wa ashita benkyou shitai desu. (Bill wants to study tomorrow.)
• Anata wa yakusoku shimashita. (You promised.)
• Hiromi wa shimpai shimasen deshita. (Hiromi didn't worry.)

This should be enough about kuru and suru for the time being. Now that they have been introduced you will see them pop up from time to time in future lessons. Just remember that they are irregular and do not follow the same rules as the other verbs.