Hello,<br/><br/>I have to rewrite the following sentences, changing the nouns and pronouns into their plural forms.<br/><br/>1. A rose plant has thorns.<br/><br/>1.a The rose plants have thorns.<br/><br/>1.b Rose plants have thorns.<br/><br/>Now I have one doubt, Shall I write as 1.a or 1.b?<br/><br/>When a sentence start with "A" for example<br/><br/>2. A book is made of paper.<br/><br/>Shall I write <br/><br/>The books are made of papers.<br/><br/> OR<br/><br/>Books are made of paper.<br/><br/>What are the rules? Please help me.<br/><br/>Thanks.