New English File Elementary recommended reading

... don't) h ave to / must not / could, comparison of adjectives, simple 'if' clauses, past continuous, tag questions, ask/tell + infinitive … s tage 3 syllabus b 1 a verage word count 10,000 1,000 ...

http://www.cavesbooks.com.tw/files/webpage/bookfile/BOOKWORMS-EnglishFile.pdf