As a C1 level speaker of English, you are expected to have a strong grasp of the grammar concepts covered from levels A1 to B2. While grammar remains an important aspect of language learning at the C1 level, the primary focus shifts towards achieving greater fluency in the language.

C1 adjectives and adverbs:

• Form compound adjectives like "She is an easy-going person.", "He has an open-minded attitude."

• Alter gradable adjectives by adding extreme adverbs such as "absolutely" and "extremely". E.g. "The movie was absolutely fascinating."

• Use past participles as post modifiers following a noun. "The book, filled with torn pages, was on the shelf."

• Enhance adverbs by using complex prepositional phrases as post modifiers. "He walked in silently, as if trying not to disturb anyone."

• Adjust adverbs by modifying them with other adverbs. "She speaks English quite fluently." "He sings beautifully well."

• Use degree adverbs ('slightly', 'a bit', 'much') to modify comparatives. "This task is slightly more challenging than the previous one."

• Utilise a broad range of stance adverbs, often at the beginning of a clause, to express an attitude or viewpoint. "Apparently, he didn't receive the memo about the meeting."

C1 present tenses:

• Use negative question form to check opinions: "Isn't it amazing how technology has advanced?"

• Use negative question form as a persuasion strategy: "Don't you find it frustrating to wait in long lines at the airport?"

• Utilise present simple with a variety of reporting verbs, particularly in academic contexts: "The study demonstrates the correlation between exercise and mental health." "The graph illustrates the decline in unemployment rates."

• Use question forms in the present continuous to ask rhetorical questions: "Are we really making a difference with our recycling efforts?"

• Use a passive non-finite '-ing' form as a subordinate clause or a noun clause to give explanatory background information. "While waiting for the bus, John realised he had forgotten his wallet."

• Use present continuous passive negative form to describe ongoing situations in the present. "In my opinion, the company is not being sufficiently innovative."

C1 conditionals:

• Create subordinate conditional clauses using the phrase 'if you should' for polite and formal contexts. "If you should require any further assistance, please do not hesitate to contact our customer support team."

• Form conditional subordinate clauses with the past perfect simple and a modal verb followed by "have" and the past participle ("-ed") to express hypothetical situations in the past, that often show regret. "If they had arrived on time, they could have caught the last train."

• Create ellipted 'if' clauses by using the '-ed' form after 'if'. "If asked, I would have helped him."

C1 past tenses:

• Use the past simple in an inverted manner using the auxiliary verb 'do' within the construction 'not only … but also'. "Not only did they visit the museum, but they also attended the art workshop."

• Use the past simple tense to intricately arrange past events in a sequential manner. "He entered the room, greeted everyone, and took a seat."

• Use the past simple tense with the auxiliary verb 'did' to emphasise a specific action or event. "We did hit our targets for this year."

• Use the politeness structure of the past simple tense 'I thought' to convey indirectness in communication. "I thought it might be better to reschedule the meeting."

• In formal contexts, invert the subject and affirmative auxiliary verb to discuss hypothetical situations in the past, frequently accompanied by regret. "Had I known about the traffic, I would have left earlier"

• Employ the complete negative forms with a wide range of verbs, particularly in formal settings. "Consequently, you have failed to fulfil your task with proper diligence, as indicated in the report."

C1 future tenses:

• Future Simple: To form the negative form, use "shall not". "I shall not attend the meeting tomorrow."

• Future Simple: Use "be" + "going to" with a wider range of adverbs, especially adverbs of certainty, placed in the usual middle position. "She is definitely going to pass the exam."

• Present Simple: Use it with "by the time" to refer to future events. "By the time you arrive, I will have finished preparing dinner."

• Future Continuous: Use it with "might" or "may" to discuss an event or activity that may be in progress at a specific or implied time in the future. "They might be traveling to Europe this time next year."

• Future Perfect: Use it with adverbs placed in the typical middle position. "By next week, I will have already completed the project."

• Future Perfect Simple: Use it with "will" to make assumptions about the present, particularly when referring to "you." "You will have already known the outcome of the game."

C1 modal verbs:

• Use "can't" or "cannot have" followed by the "-ed" form of a verb to make deductions. "She can't have forgotten her keys; they were in her bag this morning."

• Use "can" in passive reporting clauses for more formal and impersonal styles, such as in reports or academic contexts. "It can be seen that the study was conducted with meticulous care."

• Utilise expressions with "can" or "can't" to add focus or emphasise a particular point. "I can't stress enough how important it is to be prepared for the interview."

• Use "could have" followed by the "-ed" form of a verb to express disapproval or criticism. "He could have called to let us know he would be late."

• Employ the fixed expression "I dare say" to indicate that something is probably true. "I dare say she will be delighted to receive the news of her promotion."

• Use "how dare...!" to express disapproval or offence about something. "How dare you speak to me in such a disrespectful manner!"

• Use "may well" to give emphasis to something unexpected. "You may well be surprised by the outcome of the experiment."

• Use "may not have" followed by the "-ed" form of a verb to talk about possibility in the past. "She may not have realised the impact of her words at that time."

• Use "might not have" followed by the "-ed" form of a verb to express uncertainty about a past event. "He might not have recognised her in the crowd."

• Use "might" followed by "but" to console or justify a situation. "I know it's a challenging situation, but you might try to see it from his perspective."

• Use "might not have" followed by the "-ed" form of a verb to discuss possibility with a past reference. "He might not have finished the project by the deadline."

• Use "should" after "if" to talk about possible situations in the future. "If it rains tomorrow, we should bring umbrellas."

• Use "should" with an inverted subject to refer to possible situations, especially in formal contexts. "Should there be any further questions, please do not hesitate to contact me."

• Expand the range of adverbs used with "would" (e.g. absolutely, gladly, easily, patiently, happily). "He would frequently visit his grandmother in the countryside."

C1 questions:

• Alternative Questions with Ellipsis: Can construct alternative questions with two clauses, using ellipsis in the second clause, often as a means of hedging. "Did you go to the party last night or...?"

• Extreme Alternative Questions: Can create alternative questions using an extreme alternative to add greater pragmatic force. "Are you going to finish the project on time or never complete it?"

• Question Tags with 'there' + 'be': Can utilise affirmative and negative forms of question tags with 'there' + 'be'. "There's a book on the table, isn't there?"

• 'Wh-' Questions as a Focusing Device: Can employ 'wh-' questions as a focusing device, particularly in a narrative or argument context. "Who is responsible for this mess?" "Why should we support this policy?"