asagohan ha tabemasu is wrong. asagohan wo tabemasu means I eat breakfast. I am eating breakfast means asagohan wo tabeteimasu. I like Eliot's answer very much!!

With the sentense "I'm having breakfast", If you mean "I'm having breakfast right now", it should be "Watashi wa ima asagohan wo tabeteirutokorodesu". If you mean "I'm about to have breakfast", it should be "Watashi wa asagohan wo taberutokorodesu". If you mean "( I may not be able to have lunch, so I should/will have breakfast. And) I'm having breakfast", it should be "asagohan wa tabemasu". Please note that "ha" is "は", the pronounciation is "wa".

Neither. Ima asagohan no massai chuu. Now that's stylish. LOL

Hi! Let me first put these two sentence in Japanese so we can see it in a more clear way. (1) asagohan ha tabemasu 朝ご飯は食べます。 (2) asagohan wo tabemasu 朝ご飯を食べます。 (1) uses word "は" to emphasize the noun "朝ご飯". Usually when you want to use "は" instead of "を", you may want to compare two or more things or you want to use a negative expression. In this case, you may say: 朝ご飯は食べますが、晩ご飯は食べません。 I eat breakfast, but I don't eat dinner. 朝ご飯は食べません。 I don't eat dinner. (2) is more common expression when you simply just want to say you eat breakfast.

the 2nd one