Questions

'No sooner' is always followed by ‘Than’ and the verb comes before the subject. Thus, the sentence is grammatically and contextually correct. Thus, the correct formation would be, ‘No sooner had he completed his first novel than he fell seriously ill’.

If some action has started in the past and is still continuing, then present perfect continuous tense should be used instead of present continuous tense. So, the phrase ‘am living’ needs to be replaced with ‘have been living’ to make the sentence contextually correct. Thus, the correct formation would be, ‘I have been living in Bombay for the last ten years’.

‘Were’ needs to be replaced with ‘was’ to make the sentence grammatically correct. This is because, ‘If the subjects are joined by as well as, with, along with, together with, and not, in addition to, but, besides, except, rather than, accompanied by, like, unlike, no less than, nothing but, led by, headed by, guided by, controlled by, governed by,etc.. Then the verb will agree with the first subject’ Thus, the correct sentence would be, ‘Sita with all her sisters was here’.