Grammar connections
Unit 10 Present continuous: am/is/are + verb-ing for actions happening now or temporary activity around now. Negatives put not after be; questions put be before the subject. “The students are checking the lights now.” Compare a routine “They check the lights every day” with a current action. Spell write→writing, run→running. A stative verb such as know is normally not continuous in this meaning.
Unit 11 Future simple: will + base verb for predictions and decisions; negative will not/won’t; question Will + subject + base verb? A prediction is not a proven fact: “Some buses may become driverless” is more cautious than claiming every bus will change. Possessive pronouns: mine, yours, his, hers, ours, theirs stand without a following noun: “This bicycle is hers.” Possessive adjectives require a noun: her bicycle.
Unit 12 Articles: a before a consonant sound, an before a vowel sound, for a singular countable noun mentioned without a specific identity: a castle, an island, a university (/juː/ starts with a consonant sound). The identifies something already known or unique in context: “I saw a castle. The castle was old.” Use the in names such as the United Kingdom and the United States; normally no article before Australia or Canada. Do not infer an article from a letter alone.