Ilike eat ice cream,but i mustn't eat too much ice cream. i can write,but i don't like write. do you want go there? -no,i don't.but i must go there. she wants watch tv,but she must do her homework. i can help you,but i must not do it.

I can ... write,but i don't like ..TO  write.
Do you want TO go there? -No,i don't.But i must ... go there.
She wants TO watch TV,but she must ... do her homework.
I can ... help you,but i must not TO do it.