have – there are two people, so it is <u>plural</u>
are – it refers to a cousin and the narrator, so <u>plural </u>
are – Meeta is singular, but sisters are <u>plural</u>, therefore answer must be used for plural noun
was – even though the jury is consisting of the more than one person, t<u>hey are treated as the singular group</u>
by the rules, both are or is can be used, however, are sounds more natural with the plural noun "books"
was – <u>it refers to the name of the book</u> which is <em>The Midnight's Children</em> not the nook itself, so it is <u>singular </u>
was – it<u> refers to the quality which is singular,</u> not the sarees
is – <u>it refers to the size, a singular</u>, not the curtains
is –<u> it refers to the sum</u>, which is a <u>singular </u>noun
was – each of the candidates is <u>singular</u>
have – Mohit and the friends are <u>plural </u>number of people
is –<u> it refers to the distance</u>, which is a <u>singular </u>noun
was – a women is a <u>singular</u>
<u>This one is not the full question</u>, the full one should be "<em>Neither the teacher nor his students (is/are) in the class</em>" The answer is are because it refers to the <u>plural</u> number of people with teacher and the student<u>s</u>
was – it refers to <u>only one person</u>, as it says "<em>one </em>of the boys", therefore it is <u>singular</u>
No they aren't proper to use in writing class they are considered slang. It would show your teacher that your not interested in sounding educated and proper. Hope this helps!
