YOU SAID:
I really should be doing my homework.
INTO JAPANESE
私は本当に宿題をしているはずです。
BACK INTO ENGLISH
I should be doing my homework.
INTO JAPANESE
私は宿題をやっている必要があります。
BACK INTO ENGLISH
I'm doing my homework.
INTO JAPANESE
宿題をしてるの
BACK INTO ENGLISH
I'm doing my homework.
Come on, you can do better than that.